A machine whose presence says online is heard now; last heard is otherwise the later of last_seen and the presence time (issue 1156)

The old pin named mesh-sdk #28's head, which no branch holds, so a fresh
download of the controller could not fetch it.

.gitignore

@@ -3,3 +3,8 @@
 # A built binary. The lab writes one here when pointed at the repository root by mistake;
 # built artifacts belong in build/, which is already ignored.
 /mesh-builder
+/mesh-controller
+/postgres-provisioner
+/redis-provisioner
+# And where `go build` in cmd/mesh-controller leaves it (novox/hq issue 233).
+/cmd/mesh-controller/mesh-controller

Dockerfile

@@ -1,4 +1,11 @@
-# The control plane's image.
+# The Go it builds with, pinned here because genesis builds this file with no arguments (novox/hq
+# issue 223) — the Makefile passes the same digest. A tag older than go.mod asks for is how
+# `make image` broke once before (issue 146).
+ARG GO_BASE=golang@sha256:8ac98ca534ac3f51e1f420a1dd2c15e74c75cfa0f23f3ad27eb5d7236c349a0c
+# The control plane's image — for genesis and the lab only. The mesh runs the controller as a Go
+# bundle the host starts as a process (module.json; novox/hq issue 213), and builds no image of it.
+# Genesis builds this file and raises it as the container the process replaces on the first push
+# (mesh-host internal/bootstrap, novox/hq issue 223).
 #
 # novox/hq ADR 0006: this image is pinned by digest in the bundle the host carries, fetched on a
 # machine where no mesh exists yet, and run before there is anything to check it against. So it
@@ -11,16 +18,20 @@
 # (novox/hq ADR 0004). Adding them "just in case" would put a trust store in the one image whose
 # whole argument is that it contains nothing to reason about.
 
-FROM golang:1.25-alpine AS build
+FROM ${GO_BASE} AS build
 WORKDIR /src
 
-# Dependencies first, so a change to the source does not refetch them.
+# **Nothing is fetched** (novox/hq to-be 45 Phase 1): every dependency is in vendor/, committed, so
+# the image builds from this repository alone — the host's validator among them, whose module no
+# public proxy is asked for. Dependencies first, so a change to the source does not re-copy them.
 COPY go.mod go.sum ./
-RUN go mod download
+COPY vendor/ vendor/
 
+# `COPY . .` brings `.git` along, so Go is told not to stamp the commit: the version is said by -X, and a
+# rebuild of an unchanged program is the same bytes (novox/hq ADR 0267 rule 6, issue 363).
 COPY . .
 ARG VERSION=development
-RUN CGO_ENABLED=0 go build -trimpath \
+RUN CGO_ENABLED=0 GOFLAGS=-mod=vendor GOPROXY=off go build -trimpath -buildvcs=false \
         -ldflags "-s -w -X main.version=${VERSION}" \
         -o /mesh-controller ./cmd/mesh-controller
 

Makefile

@@ -27,8 +27,22 @@ build:
 IMAGE ?= mesh-controller:$(VERSION)
 DEV_TAG ?= mesh-controller:development
 
+# The Go base the image is built on.
+#
+# **`make image` was broken and stayed broken**, because the Dockerfile's fallback base was a Go
+# older than go.mod asks for: every build died at `go mod download` with "go.mod requires go >=
+# 1.26.0", and the pipeline never saw it because the pipeline passes the declared base in. Anybody
+# building the image by hand hit it and had to find the digest themselves (novox/hq 04-ISSUES/146,
+# what it cost).
+#
+# **Pinned here since the manifest stopped building an image** (novox/hq issue 213): the mesh builds
+# the controller as a Go bundle with its own toolchain, and only `make image` — genesis and the lab —
+# still needs a Go base. The digest is the one the manifest declared until then.
+GO_BASE ?= golang@sha256:8ac98ca534ac3f51e1f420a1dd2c15e74c75cfa0f23f3ad27eb5d7236c349a0c
+
 image:
-	docker build --build-arg VERSION=$(VERSION) -t $(IMAGE) -t $(DEV_TAG) .
+	@test -n "$(GO_BASE)" || { echo "no GO_BASE; pass GO_BASE=<image>"; exit 1; }
+	docker build --build-arg GO_BASE=$(GO_BASE) --build-arg VERSION=$(VERSION) -t $(IMAGE) -t $(DEV_TAG) .
 	@echo
 	@docker image inspect $(IMAGE) --format 'built {{.RepoTags}}  {{.Size}} bytes'
 
@@ -38,7 +52,8 @@ BUILDER_IMAGE ?= mesh-builder:$(VERSION)
 BUILDER_DEV_TAG ?= mesh-builder:development
 
 builder-image:
-	docker build -f cmd/mesh-builder/Dockerfile -t $(BUILDER_IMAGE) -t $(BUILDER_DEV_TAG) .
+	@test -n "$(GO_BASE)" || { echo "no GO_BASE; pass GO_BASE=<image>"; exit 1; }
+	docker build --build-arg GO_BASE=$(GO_BASE) -f cmd/mesh-builder/Dockerfile -t $(BUILDER_IMAGE) -t $(BUILDER_DEV_TAG) .
 	@echo
 	@docker image inspect $(BUILDER_IMAGE) --format 'built {{.RepoTags}}  {{.Size}} bytes'
 
@@ -48,7 +63,7 @@ PROVISIONER_IMAGE ?= mesh-provision-postgres:$(VERSION)
 PROVISIONER_DEV_TAG ?= mesh-provision-postgres:development
 
 provisioner-image:
-	docker build -f examples/postgres-provisioner/Dockerfile \
+	docker build --build-arg GO_BASE=$(GO_BASE) -f examples/postgres-provisioner/Dockerfile \
 		-t $(PROVISIONER_IMAGE) -t $(PROVISIONER_DEV_TAG) .
 	@echo
 	@docker image inspect $(PROVISIONER_IMAGE) --format 'built {{.RepoTags}}  {{.Size}} bytes'
@@ -59,7 +74,7 @@ OBJECTSTORE_IMAGE ?= mesh-provision-objectstore:$(VERSION)
 OBJECTSTORE_DEV_TAG ?= mesh-provision-objectstore:development
 
 objectstore-image:
-	docker build -f examples/objectstore-provisioner/Dockerfile \
+	docker build --build-arg GO_BASE=$(GO_BASE) -f examples/objectstore-provisioner/Dockerfile \
 		-t $(OBJECTSTORE_IMAGE) -t $(OBJECTSTORE_DEV_TAG) .
 	@echo
 	@docker image inspect $(OBJECTSTORE_IMAGE) --format 'built {{.RepoTags}}  {{.Size}} bytes'
@@ -70,7 +85,7 @@ REDIS_PROVISIONER_IMAGE ?= mesh-provision-redis:$(VERSION)
 REDIS_PROVISIONER_DEV_TAG ?= mesh-provision-redis:development
 
 redis-provisioner-image:
-	docker build -f examples/redis-provisioner/Dockerfile \
+	docker build --build-arg GO_BASE=$(GO_BASE) -f examples/redis-provisioner/Dockerfile \
 		-t $(REDIS_PROVISIONER_IMAGE) -t $(REDIS_PROVISIONER_DEV_TAG) .
 	@echo
 	@docker image inspect $(REDIS_PROVISIONER_IMAGE) --format 'built {{.RepoTags}}  {{.Size}} bytes'
@@ -80,25 +95,43 @@ PROXY_IMAGE ?= mesh-route-proxy:$(VERSION)
 PROXY_DEV_TAG ?= mesh-route-proxy:development
 
 proxy-image:
-	docker build -f examples/route-proxy/Dockerfile -t $(PROXY_IMAGE) -t $(PROXY_DEV_TAG) .
+	docker build --build-arg GO_BASE=$(GO_BASE) -f modules/route-proxy/Dockerfile -t $(PROXY_IMAGE) -t $(PROXY_DEV_TAG) .
 	@echo
 	@docker image inspect $(PROXY_IMAGE) --format 'built {{.RepoTags}}  {{.Size}} bytes'
 
-# The whole gate. Raises a database, runs everything against it, and takes it down again --
-# including when the tests fail, which is why the teardown is not conditional.
-check: fmt vet postgres
-	@go test ./... ; status=$$? ; $(MAKE) postgres-stop ; exit $$status
+# The whole check. Raises a database, runs the repository's own check against it -- merge-check.sh,
+# the very script `mesh/repo-check` runs -- and takes the database down again, including when the
+# check fails, which is why the teardown is not conditional and the script's exit status is the
+# target's.
+#
+# **It calls the script rather than restating it** (novox/hq issue 431): this target used to list its
+# own steps, its formatting step walked vendor/ where the script's does not, and it failed on
+# third-party code no change could fix -- so a developer's check and the gate disagreed, and the steps
+# after formatting never ran through it. The script is the one list of steps; this target only gives it
+# a database (MESH_TEST_POSTGRES, exported above).
+#
+# **Two levels** (issue 895): the unit level, `go test ./...` untagged, timed and held to a bound; and the integration
+# level, `-tags integration`, the tests that start a bus, a store or another process. Each is said with its time.
+#
+# **Packages in parallel, under the race detector, each test on a bus of its own** (internal/testbus),
+# as the script runs them: a bus per test, of the release the mesh runs, makes the suite the same in any
+# order, and the timeout bounds a hang to a failure with a stack, never a stalled gate.
+check: postgres
+	@sh merge-check.sh ; status=$$? ; docker rm -f $(PG_CONTAINER) >/dev/null 2>&1 || true ; exit $$status
 
-# Without a database the live tests skip rather than fail, so this is the honest subset and not
-# the gate.
+# The unit level alone (untagged: no bus, no store, no other process), which a developer runs continuously. The tests
+# that need a bus or the store carry `//go:build integration` and run in `check`, not here; without a database the
+# store's tests would skip rather than fail anyway.
 test:
-	go test ./...
+	go test -timeout 15m ./...
 
 vet:
 	go vet ./...
 
+# Quick steps for a developer, not part of `check`. The directories gofmt reads must be the ones
+# merge-check.sh lists, never `.`, which walks vendor/ (novox/hq issue 431).
 fmt:
-	@unformatted=$$(gofmt -l . 2>/dev/null) ; \
+	@unformatted=$$(gofmt -l cmd internal examples) ; \
 	if [ -n "$$unformatted" ] ; then echo "not gofmt'd:" ; echo "$$unformatted" ; exit 1 ; fi
 
 postgres:

README.md

@@ -193,6 +193,13 @@ passes every check that only looks at the message.
 
 ## The image
 
+**The mesh no longer runs the controller from it** (novox/hq issue 213). The module declares a Go
+bundle, `controller`, which the host on the controller's machine unpacks and runs as the process
+`mesh-controller` under the account of the same name (ADR 0188 §1, §3). The image stays for what
+still runs a container of the controller: genesis, which raises the first controller from it and
+installs the module from its manifest (mesh-host `internal/bootstrap`), and the lab. Neither is the
+mesh's own build any more — `make image` builds it.
+
 `FROM scratch`, holding one statically linked binary and nothing else — no shell, no package
 manager, no libc, no CA certificates.
 

RELEASE-57.md

@@ -0,0 +1,6 @@
+# Release 57: config and provisioning
+
+This branch carries the work of hq design 57 (ADR 0348, ADR 0349) in this repository. Each package
+merges here through its own reviewed pull request; the branch reaches main as one pull request, in one
+delivery group with the branch of the same name in mesh-controller, mesh-host, mesh-sdk, mesh-catalog
+and hq, after a rehearsal in the lab. This file is deleted by the last commit before that pull request.

check-nested-modules.sh

@@ -0,0 +1,29 @@
+#!/bin/sh
+# The unit tests of every Go module of its own below this repository's root, run from the root, for merge-check.sh
+# and for the test that tries it on a tree (merge_check_nested_test.go). Its own file so that the test needs no
+# particular merge-check.sh: the check that judges a change to merge-check.sh is main's.
+set -eu
+cgo="${cgo:-0}"
+race="${race:-}"
+
+# nested_modules vets and tests every Go module of its own below the root, `modules/<name>/go.mod` (novox/hq ADR 0420
+# §5, issue 1025): `./...` stops at a nested go.mod, so a module that lives whole in this repository would have its
+# unit tests run by nobody. None is a pass. Each runs in its own directory, outside the vendor directory this
+# repository's own packages are built from; a nested module vendors what the forge holds (its own `vendor/`, so the
+# check runs offline), as this repository's root module does (issue 1019). A failing module fails the check; the others are still run.
+nested_modules() {
+	nested=0
+	for gomod in modules/*/go.mod; do
+		[ -e "$gomod" ] || continue
+		dir=$(dirname "$gomod")
+		echo "nested module $dir:"
+		if ! (cd "$dir" && GOFLAGS= CGO_ENABLED=0 go vet ./... &&
+			GOFLAGS= CGO_ENABLED="${cgo:-0}" go test ${race:-} -count=1 -timeout 30m ./...); then
+			echo "nested module $dir FAILED"
+			nested=1
+		fi
+	done
+	return $nested
+}
+
+nested_modules

cmd/mesh-builder/Dockerfile

@@ -1,17 +1,19 @@
+ARG ALPINE_BASE=alpine:3
+ARG GO_BASE=golang:1.25-alpine
 # The builder, as a module ships one.
 #
 # Not FROM scratch, unlike the control plane: this one runs git and a container client, so it
 # needs a filesystem with them on it. That is the honest cost of a machine whose job is to build —
 # and it is why building is a MODULE on a machine that has a runtime rather than something the
 # control plane does (novox/hq ADR 0005).
-FROM golang:1.25-alpine AS build
+FROM ${GO_BASE} AS build
 WORKDIR /src
 COPY go.mod go.sum ./
 RUN go mod download
 COPY . .
-RUN CGO_ENABLED=0 go build -trimpath -ldflags '-s -w' -o /mesh-builder ./cmd/mesh-builder
+RUN CGO_ENABLED=0 go build -trimpath -buildvcs=false -ldflags '-s -w' -o /mesh-builder ./cmd/mesh-builder
 
-FROM alpine:3
+FROM ${ALPINE_BASE}
 # git to clone what it is asked to build, and the docker client to build and push it. The daemon
 # is the machine's, reached through its socket — a build machine shares the runtime it was given
 # rather than running one inside itself.

cmd/mesh-builder/busy.go

@@ -0,0 +1,146 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+)
+
+// **The build agent says whether it is busy, and being asked drains it** (novox/hq ADR 0335 §1, §5). Its
+// container declares `busy` as `mesh-builder busy`: the node-engine runs it inside the container before it
+// replaces it. It exits 0 while a build is in hand and 1 when none is; and from the first ask the agent takes
+// no new build request, so its answer ends once the build in hand ends — a replaced builder finishes the check
+// it runs, instead of the build queue handing it out again from the start (issue 594).
+//
+// Two marks in the container's own temporary directory, as the ready mark (ready.go): a new container starts
+// without them, and a restarted one removes them before it takes work again.
+//
+//   - in hand: written by the agent when it claims a request, before it reads whether it is drained; removed
+//     when the build ends.
+//   - drained: written by the ask, before it reads whether a build is in hand.
+//
+// Each side writes its own mark before it reads the other's, so an ask racing a fetch sees the build in hand,
+// or the agent sees the drain and hands the request back; never neither.
+
+func inHandMark() string { return filepath.Join(os.TempDir(), "mesh-builder.in-hand") }
+func drainMark() string  { return filepath.Join(os.TempDir(), "mesh-builder.drained") }
+
+// The drain lapses when no ask has come for drainLapse: the node-engine asks every 20 seconds for as long as it
+// really waits, so an agent whose replacement was withdrawn — the declaration put back, the walk stopped —
+// takes work again rather than staying drained for ever (review of ADR 0335). And an agent drained for longer
+// than the node-engine's bound and the slack says it is not ready: the replacement it was drained for never
+// came, which is a fault to see.
+const (
+	drainLapse   = 2 * time.Minute
+	drainTooLong = 15*time.Minute + 5*time.Minute
+)
+
+// drainedAt is when the drain began and when it was last asked, from its mark; false when there is no mark.
+func drainedAt() (began, asked time.Time, ok bool) {
+	info, err := os.Stat(drainMark())
+	if err != nil {
+		return time.Time{}, time.Time{}, false
+	}
+	asked = info.ModTime()
+	began = asked
+	if raw, err := os.ReadFile(drainMark()); err == nil {
+		if t, err := time.Parse(time.RFC3339, strings.TrimSpace(string(raw))); err == nil && !t.After(asked) {
+			began = t
+		}
+	}
+	return began, asked, true
+}
+
+// drained says the agent was asked whether it is busy within drainLapse: it takes no new build request.
+func drained() bool { return drainedSince(time.Now()) }
+
+func drainedSince(now time.Time) bool {
+	_, asked, ok := drainedAt()
+	return ok && now.Sub(asked) < drainLapse
+}
+
+// drainedTooLong is the health check's second half: nil unless the agent has been drained, asked all along, for
+// longer than its node-engine's bound and the slack.
+func drainedTooLong(now time.Time) error {
+	began, asked, ok := drainedAt()
+	if !ok || now.Sub(asked) >= drainLapse || now.Sub(began) <= drainTooLong {
+		return nil
+	}
+	return fmt.Errorf("drained since %s and still asked: the replacement its node-engine waits for has not come "+
+		"within %s (novox/hq ADR 0335)", began.UTC().Format(time.RFC3339), drainTooLong)
+}
+
+// claim marks a request in hand, unless the agent is drained: then nothing is in hand, and the request goes
+// back to the queue.
+func claim() bool {
+	// Made, never written over: one build at a time, and a mark already there is a build in hand.
+	f, err := os.OpenFile(inHandMark(), os.O_WRONLY|os.O_CREATE|os.O_EXCL, 0o644)
+	if err != nil {
+		// Unmarked, an ask would say idle while this build runs: the build is not taken.
+		fmt.Fprintf(os.Stderr, "cannot mark a build in hand (%s), so it is handed back: %v\n", inHandMark(), err)
+		return false
+	}
+	_, err = f.WriteString(time.Now().UTC().Format(time.RFC3339) + "\n")
+	if closeErr := f.Close(); err == nil {
+		err = closeErr
+	}
+	if err != nil {
+		_ = os.Remove(inHandMark())
+		fmt.Fprintf(os.Stderr, "cannot mark a build in hand (%s), so it is handed back: %v\n", inHandMark(), err)
+		return false
+	}
+	if drained() {
+		_ = os.Remove(inHandMark())
+		fmt.Fprintln(os.Stderr, "asked whether busy, so this agent takes no new build: handed back")
+		return false
+	}
+	return true
+}
+
+// holding says what is in hand, for the ask to print: written once the request is read.
+func holding(what string) {
+	_ = os.WriteFile(inHandMark(), []byte(time.Now().UTC().Format(time.RFC3339)+" "+what+"\n"), 0o644)
+}
+
+// released ends the build in hand.
+func released() {
+	if err := os.Remove(inHandMark()); err != nil && !errors.Is(err, os.ErrNotExist) {
+		fmt.Fprintf(os.Stderr, "cannot remove the mark of the build in hand (%s): %v\n", inHandMark(), err)
+	}
+}
+
+// undrained clears both marks at the start of a holder: a container started again is asked afresh.
+func undrained() error {
+	for _, mark := range []string{drainMark(), inHandMark()} {
+		if err := os.Remove(mark); err != nil && !errors.Is(err, os.ErrNotExist) {
+			return fmt.Errorf("cannot remove %s: %w", mark, err)
+		}
+	}
+	return nil
+}
+
+// busy is the ask: it drains the agent, then says whether a build is in hand. Nil — exit 0 — while one is.
+func busy() (string, error) {
+	// The mark keeps when the drain began while it is asked within drainLapse, and is written again on every
+	// ask: its time is the last ask.
+	began := time.Now().UTC()
+	if was, _, ok := drainedAt(); ok && drained() {
+		began = was.UTC()
+	}
+	if err := os.WriteFile(drainMark(), []byte(began.Format(time.RFC3339)+"\n"), 0o644); err != nil {
+		// Not drained, it could take the next build: said, and answered busy only for what is in hand now.
+		fmt.Fprintf(os.Stderr, "cannot mark this agent drained (%s): %v\n", drainMark(), err)
+	}
+	held, err := os.ReadFile(inHandMark())
+	if err != nil {
+		return "", errors.New("idle: no build in hand, and this agent takes no new one")
+	}
+	since, what, _ := strings.Cut(strings.TrimSpace(string(held)), " ")
+	if what == "" {
+		what = "a build"
+	}
+	return fmt.Sprintf("busy: %s, in hand since %s; taking no new build", what, since), nil
+}

cmd/mesh-builder/busy_test.go

@@ -0,0 +1,162 @@
+package main
+
+import (
+	"os"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+)
+
+// `mesh-builder busy` answers 0 while a build is in hand and non-zero when idle, and after its first ask the
+// agent takes no new build request (novox/hq ADR 0335 §5).
+func TestBusyAnswersWhileABuildIsInHandAndDrainsTheAgent(t *testing.T) {
+	t.Setenv("TMPDIR", t.TempDir())
+	if err := undrained(); err != nil {
+		t.Fatal(err)
+	}
+	if drained() {
+		t.Fatal("an agent never asked is drained")
+	}
+	// A build is claimed and runs.
+	if !claim() {
+		t.Fatal("an agent never asked refused a build")
+	}
+	holding("novox/mesh-controller (check-280)")
+	said, err := busy()
+	if err != nil || !strings.Contains(said, "novox/mesh-controller (check-280)") {
+		t.Fatalf("an agent with a build in hand did not answer busy with what it holds: %q %v", said, err)
+	}
+	// From that ask on it takes nothing new: the fetch is not made, and one fetched is handed back.
+	if !drained() {
+		t.Fatal("the ask did not drain the agent")
+	}
+	if claim() {
+		t.Fatal("a drained agent took a new build")
+	}
+	// The build in hand is still in hand after the refused claim, and busy goes on saying so.
+	if _, err := busy(); err != nil {
+		t.Fatalf("a refused claim ended the build in hand: %v", err)
+	}
+	// It ends: idle, and still drained.
+	released()
+	if _, err := busy(); err == nil {
+		t.Fatal("an agent with nothing in hand answered busy")
+	}
+	if claim() {
+		t.Fatal("a drained agent took a build after its last one ended")
+	}
+	// Started again, it is asked afresh.
+	if err := undrained(); err != nil {
+		t.Fatal(err)
+	}
+	if drained() || !claim() {
+		t.Fatal("a holder started again is still drained")
+	}
+	released()
+}
+
+// An ask racing a fetch sees the build in hand, or the agent sees the drain and hands the request back: never
+// neither, which would replace the container under a build just taken.
+func TestAnAskRacingAFetchNeverMissesTheBuild(t *testing.T) {
+	t.Setenv("TMPDIR", t.TempDir())
+	for i := 0; i < 200; i++ {
+		if err := undrained(); err != nil {
+			t.Fatal(err)
+		}
+		var claimed bool
+		var askErr error
+		var wg sync.WaitGroup
+		wg.Add(2)
+		go func() { defer wg.Done(); claimed = claim() }()
+		go func() { defer wg.Done(); _, askErr = busy() }()
+		wg.Wait()
+		if claimed && askErr != nil {
+			t.Fatalf("round %d: the agent took a build and the ask said idle", i)
+		}
+		released()
+	}
+}
+
+// A drain no longer asked lapses: an agent whose replacement was withdrawn after the first ask (a put-back, a
+// revert, a stopped walk) takes work again after drainLapse, rather than staying drained with its health green.
+func TestADrainNoLongerAskedLapses(t *testing.T) {
+	t.Setenv("TMPDIR", t.TempDir())
+	if err := undrained(); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := busy(); err == nil {
+		t.Fatal("an idle agent answered busy")
+	}
+	if !drained() || claim() {
+		t.Fatal("an agent just asked takes work")
+	}
+	// The last ask was three minutes ago.
+	old := time.Now().Add(-3 * time.Minute)
+	if err := os.Chtimes(drainMark(), old, old); err != nil {
+		t.Fatal(err)
+	}
+	if drained() {
+		t.Fatal("a drain no longer asked for three minutes still holds")
+	}
+	if !claim() {
+		t.Fatal("an agent whose drain lapsed takes no work")
+	}
+	released()
+}
+
+// An agent drained, and asked all along, for longer than its node-engine's bound and the slack is not ready: the
+// replacement it was drained for never came. One asked again after a lapse starts a new drain.
+func TestAnAgentDrainedTooLongIsNotReady(t *testing.T) {
+	t.Setenv("TMPDIR", t.TempDir())
+	if err := undrained(); err != nil {
+		t.Fatal(err)
+	}
+	taking("mesh-build-machine")
+	if _, err := busy(); err == nil {
+		t.Fatal("an idle agent answered busy")
+	}
+	now := time.Now()
+	if err := drainedTooLong(now); err != nil {
+		t.Fatalf("an agent drained a moment ago is not ready: %v", err)
+	}
+	// The drain began 25 minutes ago, and the node-engine asked a moment ago.
+	began := now.Add(-25 * time.Minute).UTC().Format(time.RFC3339)
+	if err := os.WriteFile(drainMark(), []byte(began+"\n"), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	err := drainedTooLong(time.Now())
+	if err == nil || !strings.Contains(err.Error(), "has not come") {
+		t.Fatalf("an agent drained for 25 minutes reads ready: %v", err)
+	}
+	// Each ask keeps when the drain began.
+	if _, err := busy(); err == nil {
+		t.Fatal("an idle agent answered busy")
+	}
+	if err := drainedTooLong(time.Now()); err == nil {
+		t.Fatal("an ask started the drain again")
+	}
+	// The asks stopped: the drain lapsed, and so did the fault.
+	old := time.Now().Add(-3 * time.Minute)
+	if err := os.Chtimes(drainMark(), old, old); err != nil {
+		t.Fatal(err)
+	}
+	if err := drainedTooLong(time.Now()); err != nil {
+		t.Fatalf("a lapsed drain still reads not ready: %v", err)
+	}
+}
+
+// An ask this build does not know exits non-zero: an older image asked `busy` reads idle, not busy for the
+// node-engine's whole bound.
+func TestAnUnknownCommandFails(t *testing.T) {
+	was := os.Args
+	t.Cleanup(func() { os.Args = was })
+	os.Args = []string{"mesh-builder", "some-later-word"}
+	if err := run(); err == nil {
+		t.Fatal("an unknown command exited 0")
+	}
+	os.Args = []string{"mesh-builder", "help"}
+	if err := run(); err != nil {
+		t.Fatalf("help failed: %v", err)
+	}
+}

cmd/mesh-builder/check_spec_test.go

@@ -0,0 +1,38 @@
+package main
+
+import (
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/builder"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// The build seat hands the check the judge cache the build agent declares (MESH_JUDGE_CACHE), never a path of its own.
+func TestTheBuildSeatHandsTheCheckTheJudgeCacheItDeclares(t *testing.T) {
+	t.Setenv("MESH_JUDGE_CACHE", "/var/lib/mesh/build-agent/judge-cache")
+	if got := judgeCache(); got != "/var/lib/mesh/build-agent/judge-cache" {
+		t.Fatalf("the judge cache the manifest declares is read as %q", got)
+	}
+	t.Setenv("MESH_JUDGE_CACHE", "")
+	if got := judgeCache(); got != "" {
+		t.Fatalf("with no judge cache declared, %q is used", got)
+	}
+}
+
+// The siblings a check is asked to read reach the build seat's spec and, as read, the outcome (novox/hq ADR 0382).
+func TestTheSiblingsAnAskNamesReachTheSpecAndTheOutcome(t *testing.T) {
+	spec := checkSpecOf(link.BuildRequest{Check: &link.CheckRequest{Owner: "novox", Repo: "mesh-host", Base: "main",
+		Siblings:        []link.CheckSibling{{Repository: "novox/mesh-controller", Number: 346, Head: "a", Base: "main", Dir: "mesh-controller"}},
+		SiblingsUnknown: "why"}})
+	if len(spec.Siblings) != 1 || spec.Siblings[0] != (builder.Sibling{Repository: "novox/mesh-controller", Number: 346,
+		Head: "a", Base: "main", Dir: "mesh-controller"}) || spec.SiblingsUnknown != "why" {
+		t.Fatalf("the spec reads %+v", spec)
+	}
+	out := siblingsOut([]builder.JudgedSibling{{Repository: "novox/mesh-controller", Number: 346, Head: "a", Base: "main", BaseCommit: "b"}})
+	if len(out) != 1 || out[0].BaseCommit != "b" || out[0].Number != 346 {
+		t.Fatalf("the outcome reads %+v", out)
+	}
+	if plain := checkSpecOf(link.BuildRequest{Check: &link.CheckRequest{Owner: "o", Repo: "r"}}); plain.Siblings != nil {
+		t.Fatalf("a request that names none has siblings %+v", plain.Siblings)
+	}
+}

cmd/mesh-builder/holder.go

@@ -0,0 +1,433 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/nats-io/nats.go/micro"
+
+	"github.com/novox/mesh-controller/internal/builder"
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// What a holder of the build seat answers for, on its own machine (novox/hq ADR 0219).
+//
+// **The queue is the controller's; the build running here is this machine's.** The controller can
+// see and change what waits in the seat's queue, but an ask a holder already took is a process tree
+// on this machine and containers in this machine's runtime, and only this machine can end them. So
+// the holder serves four verbs on the seat's subjects for this machine: what it is building, kill
+// it, pause, resume.
+//
+// **One build at a time** (ADR 0190), which is also what builder.Said assumes — a package global
+// set per build — so "the build running here" is one or none, and kill names it by id so a call
+// that arrives as one build ends and the next begins cannot end the wrong one.
+
+// holder is this machine's state as a holder of the build seat.
+type holder struct {
+	on, seat string
+	// workspace is where the paused flag is kept, so a holder restarted while paused stays paused
+	// rather than silently taking work again.
+	workspace string
+	// say publishes this machine's state: whether it takes work (link.HolderState).
+	say func(link.HolderState) error
+	// remove runs what a kill needs outside the build: the containers left behind.
+	remove builder.Runner
+	// scratch is where check builds are kept (novox/hq ADR 0350 §5): what the week's sweep lets go of. Nil where
+	// this machine publishes to no artifact store.
+	scratch builder.Scratch
+
+	mu      sync.Mutex
+	paused  bool
+	running *running
+}
+
+// running is the build this machine is doing.
+type running struct {
+	request link.BuildRequest
+	step    string
+	started time.Time
+	cancel  context.CancelFunc
+	killed  bool
+	// returned is the build's own work having ended, before a kill or not; outcome is what was then
+	// announced, and announced whether it went out.
+	returned  bool
+	outcome   string
+	announced bool
+	done      chan struct{}
+}
+
+// pausedFile is where the flag lives in the workspace.
+func pausedFile(workspace string) string { return filepath.Join(workspace, ".mesh-builder-paused") }
+
+// newHolder reads the paused flag the workspace keeps.
+func newHolder(on, seat, workspace string, say func(link.HolderState) error) *holder {
+	h := &holder{on: on, seat: seat, workspace: workspace, say: say, remove: plainRun}
+	if _, err := os.Stat(pausedFile(workspace)); err == nil {
+		h.paused = true
+	}
+	return h
+}
+
+// Paused is asked by the taking loop before every fetch.
+func (h *holder) Paused() bool {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	return h.paused
+}
+
+// setPaused records the flag in the workspace first and then in memory, so what this holder says
+// it is and what it would be after a restart never differ.
+func (h *holder) setPaused(paused bool) error {
+	path := pausedFile(h.workspace)
+	if paused {
+		if err := os.MkdirAll(h.workspace, 0o755); err != nil {
+			return err
+		}
+		if err := os.WriteFile(path, []byte(time.Now().UTC().Format(time.RFC3339)+"\n"), 0o644); err != nil {
+			return fmt.Errorf("cannot keep the paused flag in %s: %w", path, err)
+		}
+	} else if err := os.Remove(path); err != nil && !errors.Is(err, os.ErrNotExist) {
+		return fmt.Errorf("cannot remove the paused flag %s: %w", path, err)
+	}
+	h.mu.Lock()
+	h.paused = paused
+	h.mu.Unlock()
+	h.announce()
+	return nil
+}
+
+// announce says whether this machine takes work. Never fatal: the flag is kept either way, and the
+// controller reading an older state is a plan read as late rather than a build lost.
+func (h *holder) announce() {
+	if h.say == nil {
+		return
+	}
+	if err := h.say(link.HolderState{On: h.on, Paused: h.Paused(), At: time.Now().UTC().Format(time.RFC3339Nano)}); err != nil {
+		fmt.Fprintf(os.Stderr, "cannot say whether this machine takes builds: %v\n", err)
+	}
+}
+
+// stateWhilePaused says this machine's state at start, and again every while it stays paused, so
+// a pause outlives the events stream's retention.
+func (h *holder) stateWhilePaused(ctx context.Context, every time.Duration) {
+	h.announce()
+	tick := time.NewTicker(every)
+	defer tick.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-tick.C:
+			if h.Paused() {
+				h.announce()
+			}
+		}
+	}
+}
+
+// expireChecks lets go of every check build older than a week (novox/hq ADR 0350 §5), at start and every while
+// after. Every holder sweeps the one store; what one let go of, another finds gone.
+func (h *holder) expireChecks(ctx context.Context, every time.Duration, now func() time.Time) {
+	sweep := func() {
+		if h.scratch == nil {
+			return
+		}
+		n, err := h.scratch.Expire(ctx, builder.CheckBuildsKept, now())
+		switch {
+		case err != nil:
+			fmt.Fprintf(os.Stderr, "check builds older than %s: %d let go of, and not all: %v\n", builder.CheckBuildsKept, n, err)
+		case n > 0:
+			fmt.Fprintf(os.Stderr, "check builds older than %s: %d check(s)' builds let go of\n", builder.CheckBuildsKept, n)
+		}
+	}
+	sweep()
+	tick := time.NewTicker(every)
+	defer tick.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-tick.C:
+			sweep()
+		}
+	}
+}
+
+// begin records the build this machine took, with the cancel that ends it.
+func (h *holder) begin(request link.BuildRequest, cancel context.CancelFunc) *running {
+	r := &running{request: request, started: time.Now(), cancel: cancel, done: make(chan struct{})}
+	h.mu.Lock()
+	h.running = r
+	h.mu.Unlock()
+	return r
+}
+
+// end clears it, and lets a kill waiting on it know it is over.
+func (h *holder) end(r *running) {
+	h.mu.Lock()
+	if h.running == r {
+		h.running = nil
+	}
+	h.mu.Unlock()
+	close(r.done)
+}
+
+// stepped records the step a build is at, for `current`.
+func (h *holder) stepped(r *running, step string) {
+	h.mu.Lock()
+	r.step = step
+	h.mu.Unlock()
+}
+
+// currentBuild is what `current` answers.
+type currentBuild struct {
+	On      string `json:"on"`
+	Paused  bool   `json:"paused"`
+	Running *struct {
+		ID         string `json:"id"`
+		Repository string `json:"repository"`
+		Path       string `json:"path,omitempty"`
+		Ref        string `json:"ref,omitempty"`
+		Step       string `json:"step,omitempty"`
+		Started    string `json:"started"`
+		Elapsed    string `json:"elapsed"`
+	} `json:"running,omitempty"`
+	Said string `json:"said"`
+}
+
+func (h *holder) current() currentBuild {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	out := currentBuild{On: h.on, Paused: h.paused}
+	taking := "taking builds"
+	if h.paused {
+		taking = "paused, taking no new build"
+	}
+	if h.running == nil {
+		out.Said = fmt.Sprintf("%s is building nothing; %s", h.on, taking)
+		return out
+	}
+	r := h.running
+	elapsed := time.Since(r.started).Round(time.Second)
+	out.Running = &struct {
+		ID         string `json:"id"`
+		Repository string `json:"repository"`
+		Path       string `json:"path,omitempty"`
+		Ref        string `json:"ref,omitempty"`
+		Step       string `json:"step,omitempty"`
+		Started    string `json:"started"`
+		Elapsed    string `json:"elapsed"`
+	}{r.request.ID, r.request.Repository, r.request.Path, r.request.Ref, r.step,
+		r.started.UTC().Format(time.RFC3339), elapsed.String()}
+	out.Said = fmt.Sprintf("%s is building %s (%s) at %s for %s; %s",
+		h.on, r.request.Repository, r.request.ID, orNothing(r.step), elapsed, taking)
+	return out
+}
+
+// The bounds a kill keeps: each pass removing containers, and the wait for the build to end between
+// them. The worst case — 15s, 20s, 15s — is inside what the controller waits for the answer
+// (killAnswer in the controller's queue.go, 75s).
+var (
+	killRemoves = 15 * time.Second
+	killWaits   = 20 * time.Second
+)
+
+// kill ends the build with this id, if it is the one running here and still working: its context
+// cancelled — which kills each command's process group — and the containers it started removed by
+// their label, once at once and again after the build has ended, so one created while it was being
+// killed is not left. The build's own goroutine announces it failed, killed by hand, and settles the
+// ask so it is not redelivered; the answer says whether that happened.
+func (h *holder) kill(id string) (string, error) {
+	h.mu.Lock()
+	r := h.running
+	if r == nil || r.request.ID != id {
+		doing := "nothing"
+		if r != nil {
+			doing = r.request.ID
+		}
+		h.mu.Unlock()
+		return "", fmt.Errorf("%s is not building %s; it is building %s. `queue` says where an ask is", h.on, id, doing)
+	}
+	if r.returned {
+		h.mu.Unlock()
+		return "", fmt.Errorf("%s on %s has already ended on its own and is saying how; `builds` shows it", id, h.on)
+	}
+	r.killed = true
+	cancel, done := r.cancel, r.done
+	h.mu.Unlock()
+
+	cancel()
+	removed, removeErr := h.removeContainers(id)
+	ended := false
+	select {
+	case <-done:
+		ended = true
+	case <-time.After(killWaits):
+	}
+	again, againErr := h.removeContainers(id)
+	removed += again
+	if removeErr == nil {
+		removeErr = againErr
+	}
+	containers := fmt.Sprintf("%d container(s) it started removed", removed)
+	if removeErr != nil {
+		containers = "its containers could not all be listed or removed: " + removeErr.Error()
+	}
+	if !ended {
+		return fmt.Sprintf("killed %s on %s: %s; the build has not finished ending yet — `builds` says when "+
+			"its outcome is in", id, h.on, containers), nil
+	}
+	h.mu.Lock()
+	outcome, announced := r.outcome, r.announced
+	h.mu.Unlock()
+	if !announced {
+		return fmt.Sprintf("killed %s (%s) on %s: its commands ended and %s, and its outcome could not be "+
+			"announced — the ask is not settled and will be handed out again", id, r.request.Repository, h.on,
+			containers), nil
+	}
+	return fmt.Sprintf("killed %s (%s) on %s: its commands ended, %s, and its outcome announced as failed, %s — "+
+		"settled, so it is not handed to another machine", id, r.request.Repository, h.on, containers, outcome), nil
+}
+
+// removeContainers is one pass of removing what the build left, bounded.
+func (h *holder) removeContainers(id string) (int, error) {
+	cleanup, stop := context.WithTimeout(context.Background(), killRemoves)
+	defer stop()
+	return builder.RemoveContainersOf(cleanup, h.remove, id)
+}
+
+// removeLeftBehind removes, once, what earlier holders on this machine left — called before anything is
+// taken, so none of it is this holder's — and says what it did. A runtime that cannot be asked is said
+// and the holder takes work all the same: what is left is waste, not a reason to stop building.
+func (h *holder) removeLeftBehind() int {
+	cleanup, stop := context.WithTimeout(context.Background(), killRemoves)
+	defer stop()
+	n, err := builder.RemoveLeftBehind(cleanup, h.remove)
+	switch {
+	case err != nil:
+		fmt.Fprintf(os.Stderr, "could not look for containers earlier builds left on %s: %v\n", h.on, err)
+	case n > 0:
+		fmt.Fprintf(os.Stderr, "removed %d container(s) earlier builds left on %s\n", n, h.on)
+	}
+	return n
+}
+
+// returned records that the build's work ended, and says whether a kill came first — only then is
+// the build killed; an error it ended with on its own is its own outcome.
+func (h *holder) returned(r *running) bool {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+	r.returned = true
+	return r.killed
+}
+
+// said records the outcome announced, and whether it went out, for a kill to answer with.
+func (h *holder) said(r *running, outcome string, announced bool) {
+	h.mu.Lock()
+	r.outcome, r.announced = outcome, announced
+	h.mu.Unlock()
+}
+
+// handlers are the seat's verbs, as this machine answers them.
+func (h *holder) handlers() map[string]link.ToolHandler {
+	return map[string]link.ToolHandler{
+		"current": func(context.Context, json.RawMessage) (any, error) { return h.current(), nil },
+		"kill": func(_ context.Context, raw json.RawMessage) (any, error) {
+			var args struct {
+				ID string `json:"id"`
+			}
+			if err := json.Unmarshal(raw, &args); err != nil || strings.TrimSpace(args.ID) == "" {
+				return nil, errors.New("kill needs the build's id")
+			}
+			said, err := h.kill(strings.TrimSpace(args.ID))
+			if err != nil {
+				return nil, err
+			}
+			return map[string]any{"said": said}, nil
+		},
+		"pause": func(context.Context, json.RawMessage) (any, error) {
+			if err := h.setPaused(true); err != nil {
+				return nil, err
+			}
+			said := h.on + " is paused: it takes no new build until resumed"
+			if c := h.current(); c.Running != nil {
+				said += "; " + c.Running.ID + " runs on and finishes"
+			}
+			return map[string]any{"said": said, "paused": true}, nil
+		},
+		"resume": func(context.Context, json.RawMessage) (any, error) {
+			if err := h.setPaused(false); err != nil {
+				return nil, err
+			}
+			return map[string]any{"said": h.on + " takes builds again", "paused": false}, nil
+		},
+	}
+}
+
+func orNothing(s string) string {
+	if s == "" {
+		return "its start"
+	}
+	return s
+}
+
+// plainRun runs a command outside any build: no line reaches a build's log, because the build whose
+// log it would be is the one being ended.
+func plainRun(ctx context.Context, dir, name string, args ...string) (string, error) {
+	cmd := exec.CommandContext(ctx, name, args...)
+	cmd.Dir = dir
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		return string(out), fmt.Errorf("%s %s: %w: %s", name, strings.Join(args, " "), err, strings.TrimSpace(string(out)))
+	}
+	return string(out), nil
+}
+
+// announcement is what this holder answers discovery with (novox/hq ADR 0195, ADR 0197): this
+// machine's verbs of the seat, in the shape every tool runtime announces a seat's verb — kind seat,
+// the module answering, the seat, scope node, the machine, its description and argument schema — so
+// the console finds `<node>/node-build-agent.kill` by searching, as it finds any seat's verb.
+//
+// One service per machine, named for the seat and identified by the machine, so the answer is this
+// machine's four verbs and nothing more. The verbs are the compiled seat row's: a build machine has no
+// store, and what it serves is what this binary was built to serve.
+func announcement(seat, module, node string) micro.Info {
+	s, _ := catalogue.SeatNamed(seat)
+	var endpoints []micro.EndpointInfo
+	for _, v := range s.Serves {
+		schema, _ := json.Marshal(v.Input)
+		endpoints = append(endpoints, micro.EndpointInfo{
+			Name:    seat + "__" + v.Name,
+			Subject: link.NodeSeatToolSubject(seat, v.Name, node),
+			// The queue group the verbs are served in, as every runtime announces its own.
+			QueueGroup: "seat." + seat,
+			Metadata: map[string]string{
+				"kind": "seat", "module": module, "tool": v.Name, "seat": seat, "scope": "node",
+				"node": node, "interchangeable": "false", "description": v.Description, "schema": string(schema),
+			},
+		})
+	}
+	return micro.Info{
+		ServiceIdentity: micro.ServiceIdentity{Name: seat, ID: node, Version: "0.1.0",
+			Metadata: map[string]string{"seat": seat, "scope": "node", "node": node, "module": module}},
+		Description: "what the build running on " + node + " is, and ending, pausing and resuming it (novox/hq ADR 0219)",
+		Endpoints:   endpoints,
+	}
+}
+
+// moduleOf is the module a credential was issued for: its user is `<node>.<module>`.
+func moduleOf(user string) string {
+	if _, module, ok := strings.Cut(user, "."); ok && module != "" {
+		return module
+	}
+	return "build-agent"
+}

cmd/mesh-builder/holder_test.go

@@ -0,0 +1,172 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// A holder paused stays paused across its restart: the flag is kept in its workspace (novox/hq ADR
+// 0219), and what it says about itself follows.
+func TestAPausedHolderStaysPausedAcrossARestart(t *testing.T) {
+	workspace := t.TempDir()
+	var said []link.HolderState
+	h := newHolder("ace", link.TheBuildMachine, workspace, func(s link.HolderState) error {
+		said = append(said, s)
+		return nil
+	})
+	if h.Paused() {
+		t.Fatal("a new holder starts paused")
+	}
+	if _, err := h.handlers()["pause"](context.Background(), json.RawMessage(`{}`)); err != nil {
+		t.Fatal(err)
+	}
+	if !h.Paused() || len(said) != 1 || !said[0].Paused || said[0].On != "ace" {
+		t.Fatalf("paused: %v, said %+v", h.Paused(), said)
+	}
+	again := newHolder("ace", link.TheBuildMachine, workspace, nil)
+	if !again.Paused() {
+		t.Fatal("restarted, the holder forgot it was paused")
+	}
+	if _, err := again.handlers()["resume"](context.Background(), json.RawMessage(`{}`)); err != nil {
+		t.Fatal(err)
+	}
+	if newHolder("ace", link.TheBuildMachine, workspace, nil).Paused() {
+		t.Fatal("resumed, the holder came back paused")
+	}
+}
+
+// kill ends the build with that id — its context, which ends its commands — removes what it left by
+// label, and refuses an id it is not building.
+func TestKillEndsTheBuildRunningHereAndNoOther(t *testing.T) {
+	h := newHolder("ace", link.TheBuildMachine, t.TempDir(), nil)
+	var removed []string
+	h.remove = func(_ context.Context, _ string, name string, args ...string) (string, error) {
+		removed = append(removed, name+" "+strings.Join(args, " "))
+		if args[0] == "ps" {
+			return "c1\n", nil
+		}
+		return "", nil
+	}
+	kill := h.handlers()["kill"]
+	if _, err := kill(context.Background(), json.RawMessage(`{"id":"build-1"}`)); err == nil {
+		t.Fatal("killed a build while none ran")
+	}
+
+	building, cancel := context.WithCancel(context.Background())
+	r := h.begin(link.BuildRequest{ID: "build-1", Repository: "novox/a"}, cancel)
+	h.stepped(r, "image")
+	if c := h.current(); c.Running == nil || c.Running.ID != "build-1" || c.Running.Step != "image" {
+		t.Fatalf("current says %+v", c)
+	}
+	if _, err := kill(context.Background(), json.RawMessage(`{"id":"build-2"}`)); err == nil ||
+		!strings.Contains(err.Error(), "build-1") {
+		t.Fatalf("killed another id: %v", err)
+	}
+	// The build's own goroutine: it ends when its context does, as a build's commands do, and
+	// announces what came of it.
+	go func() {
+		<-building.Done()
+		if h.returned(r) {
+			h.said(r, link.KilledByHand, true)
+		}
+		h.end(r)
+	}()
+	answer, err := kill(context.Background(), json.RawMessage(`{"id":"build-1"}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if building.Err() == nil {
+		t.Fatal("the build's context was not cancelled")
+	}
+	if !r.killed {
+		t.Error("the build is not marked killed, so it would be announced as an ordinary failure")
+	}
+	said := answer.(map[string]any)["said"].(string)
+	if !strings.Contains(said, "2 container(s)") || !strings.Contains(said, "announced as failed") || !strings.Contains(said, link.KilledByHand) {
+		t.Errorf("kill said %q", said)
+	}
+	// Removed at the kill and again once the build had ended: a container made in between is caught.
+	if len(removed) != 4 || !strings.Contains(removed[0], "label=mesh.build=build-1") || !strings.Contains(removed[2], "label=mesh.build=build-1") {
+		t.Errorf("removed %v", removed)
+	}
+	if c := h.current(); c.Running != nil {
+		t.Errorf("after the kill current says %+v", c)
+	}
+}
+
+// A holder announces this machine's verbs of the seat as the console reads a seat's verb, and no more.
+func TestAHolderAnnouncesItsMachinesVerbsForTheConsole(t *testing.T) {
+	info := announcement(link.TheBuildMachine, moduleOf("ace.build-agent"), "ace")
+	if info.Name != "node-build-agent" || info.ID != "ace" || len(info.Endpoints) != 4 {
+		t.Fatalf("announced %s/%s with %d endpoints", info.Name, info.ID, len(info.Endpoints))
+	}
+	kill := info.Endpoints[1]
+	md := kill.Metadata
+	if kill.Subject != "mesh.seat.node-build-agent.tool.kill.ace" || kill.QueueGroup != "seat.node-build-agent" || md["kind"] != "seat" || md["seat"] != "node-build-agent" ||
+		md["scope"] != "node" || md["node"] != "ace" || md["tool"] != "kill" || md["module"] != "build-agent" ||
+		!strings.Contains(md["description"], "killed by hand") || !strings.Contains(md["schema"], `"id"`) {
+		t.Fatalf("kill is announced as %+v", kill)
+	}
+	body, err := json.Marshal(info)
+	if err != nil || len(body) > 8*1024 {
+		t.Fatalf("the answer is %d bytes (%v)", len(body), err)
+	}
+}
+
+// A build that ended on its own as the kill arrived says what it did: the kill is refused, and its
+// own error is its outcome. One whose outcome could not be announced is not said to be settled.
+func TestAKillArrivingAfterTheBuildEndedIsRefusedAndAnUnannouncedKillSaysSo(t *testing.T) {
+	h := newHolder("ace", link.TheBuildMachine, t.TempDir(), nil)
+	h.remove = func(context.Context, string, string, ...string) (string, error) { return "", nil }
+	_, cancel := context.WithCancel(context.Background())
+	r := h.begin(link.BuildRequest{ID: "build-1"}, cancel)
+	if killed := h.returned(r); killed {
+		t.Fatal("a build nobody killed reads as killed")
+	}
+	if _, err := h.kill("build-1"); err == nil || !strings.Contains(err.Error(), "ended on its own") {
+		t.Fatalf("killed a build that had ended: %v", err)
+	}
+	h.end(r)
+
+	building, cancel := context.WithCancel(context.Background())
+	r = h.begin(link.BuildRequest{ID: "build-2"}, cancel)
+	go func() {
+		<-building.Done()
+		if h.returned(r) {
+			h.said(r, link.KilledByHand, false)
+		}
+		h.end(r)
+	}()
+	said, err := h.kill("build-2")
+	if err != nil || strings.Contains(said, "announced as failed") || !strings.Contains(said, "could not be announced") {
+		t.Fatalf("kill said %q (%v)", said, err)
+	}
+}
+
+// **Issue 306**: a holder starting removes the containers earlier builds left on its machine, through
+// the runner a kill uses, and a runtime that cannot be asked does not stop it.
+func TestAHolderStartingRemovesWhatEarlierBuildsLeftHere(t *testing.T) {
+	h := newHolder("novox", link.TheBuildMachine, t.TempDir(), nil)
+	var removed []string
+	h.remove = func(_ context.Context, _ string, name string, args ...string) (string, error) {
+		removed = append(removed, name+" "+strings.Join(args, " "))
+		if args[0] == "ps" {
+			return "c1 build-1\nc2 build-1\nc3 check-here-2\n", nil
+		}
+		return "", nil
+	}
+	if n := h.removeLeftBehind(); n != 2 || len(removed) != 2 || removed[1] != "docker rm -f c1 c2" {
+		t.Fatalf("removed %d: %v", n, removed)
+	}
+	h.remove = func(context.Context, string, string, ...string) (string, error) {
+		return "", errors.New("no runtime")
+	}
+	if n := h.removeLeftBehind(); n != 0 {
+		t.Errorf("a runtime that cannot be asked removed %d", n)
+	}
+}

cmd/mesh-builder/once.go

@@ -84,11 +84,17 @@ func buildOnce(ctx context.Context, args []string) error {
 	}
 	fmt.Fprintln(os.Stderr)
 
-	npmrc, err := packagesFrom()
+	machine := os.Getenv("MESH_NODE")
+	if machine == "" {
+		machine, _ = os.Hostname()
+	}
+	npmrc, err := packagesFrom(machine)
 	if err != nil {
 		return err
 	}
+	fmt.Fprintf(os.Stderr, "  [packages] %s\n", saysRegistry(npmrc))
 	built, buildErr := builder.Build(ctx, builder.Command, publisher, repository, *path, *ref, where, bases, npmrc,
+		forgeFrom(),
 		func(step, message string) { fmt.Fprintf(os.Stderr, "  [%s] %s\n", step, message) })
 	if buildErr != nil {
 		return buildErr
@@ -104,6 +110,10 @@ func buildOnce(ctx context.Context, args []string) error {
 		Ref:        *ref,
 		Manifest:   built.Manifest,
 		Against:    built.Against,
+		Source:     built.Source,
+	}
+	for _, r := range built.Read {
+		out.Read = append(out.Read, readRepository{Repository: r.Repository, Ref: r.Ref})
 	}
 	for _, made := range built.Built {
 		out.Made = append(out.Made, madeArtifact{Name: made.Name, Kind: made.Kind, Reference: made.Reference})
@@ -122,14 +132,22 @@ func buildOnce(ctx context.Context, args []string) error {
 // The same fields the mesh records for a build, so a reader comparing a genesis build against an
 // ordinary one is comparing the same thing said the same way.
 type onceResult struct {
-	Module     string         `json:"module"`
-	Commit     string         `json:"commit"`
-	Repository string         `json:"repository"`
-	Path       string         `json:"path,omitempty"`
-	Ref        string         `json:"ref,omitempty"`
-	Manifest   any            `json:"manifest"`
-	Made       []madeArtifact `json:"made"`
-	Against    []string       `json:"against,omitempty"`
+	Module     string           `json:"module"`
+	Commit     string           `json:"commit"`
+	Repository string           `json:"repository"`
+	Path       string           `json:"path,omitempty"`
+	Ref        string           `json:"ref,omitempty"`
+	Manifest   any              `json:"manifest"`
+	Made       []madeArtifact   `json:"made"`
+	Against    []string         `json:"against,omitempty"`
+	Read       []readRepository `json:"read,omitempty"`
+	Source     string           `json:"source-fingerprint,omitempty"`
+}
+
+// readRepository is a repository this build read source from besides the module's own.
+type readRepository struct {
+	Repository string `json:"repository"`
+	Ref        string `json:"ref,omitempty"`
 }
 
 type madeArtifact struct {

cmd/mesh-builder/packages_test.go

@@ -0,0 +1,102 @@
+package main
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/builder"
+)
+
+// The build agent's package registry (novox/hq ADR 0336, issue 121): its npm-package-registry
+// requirement is optional, so the binding may be absent, and on genesis's node the installer seals
+// the forge it raised as one genesis document instead.
+
+// registryFiles names the three paths the build agent's environment always names, writing only those
+// given.
+func registryFiles(t *testing.T, binding, token, genesis string) {
+	t.Helper()
+	dir := t.TempDir()
+	for env, content := range map[string]string{
+		"MESH_PACKAGE_BINDING":          binding,
+		"MESH_NPM_TOKEN_FILE":           token,
+		"MESH_GENESIS_PACKAGE_REGISTRY": genesis,
+	} {
+		path := filepath.Join(dir, env)
+		t.Setenv(env, path)
+		if content != "" {
+			if err := os.WriteFile(path, []byte(content), 0o600); err != nil {
+				t.Fatal(err)
+			}
+		}
+	}
+	for _, env := range []string{"MESH_NPM_REGISTRY", "MESH_NPM_TOKEN", "MESH_NPM_USER", "MESH_NPM_SCOPE"} {
+		t.Setenv(env, "")
+	}
+}
+
+const (
+	aBinding = `{"from":"gitea","at":"anchor.mesh","as":"anchor-agent",
+	  "serves":{"scheme":"http","port":3000,"npm-path":"/api/packages/novox/npm/"}}`
+	aGenesisDocument = `{"scheme":"http","at":"127.0.0.1","port":3100,"npm-path":"/api/packages/novox/npm/",
+	  "as":"mesh-builder","password":"genesis-secret"}`
+)
+
+func TestUntilTheRequirementBindsTheGenesisDocumentIsRead(t *testing.T) {
+	registryFiles(t, "", "", aGenesisDocument)
+	n, err := packagesFrom("anchor")
+	if err != nil {
+		t.Fatalf("an absent binding beside a genesis document was refused: %v", err)
+	}
+	if n.From != builder.FromGenesis || n.Registry != "http://127.0.0.1:3100/api/packages/novox/npm/" ||
+		n.Username != "mesh-builder" || n.Password != "genesis-secret" || n.Scope != "@novox" {
+		t.Fatalf("the genesis document was not what the registry came from: %+v", n)
+	}
+	file, err := n.File()
+	if err != nil || !strings.Contains(file, "//127.0.0.1:3100/api/packages/novox/npm/:username=mesh-builder") {
+		t.Fatalf("the .npmrc is not written from the genesis document: %v\n%s", err, file)
+	}
+	if got := saysRegistry(n); !strings.Contains(got, "genesis document") {
+		t.Errorf("the log does not say the genesis document: %s", got)
+	}
+}
+
+func TestARealBindingWinsOverTheGenesisDocument(t *testing.T) {
+	registryFiles(t, aBinding, "bound-secret\n", aGenesisDocument)
+	n, err := packagesFrom("anchor")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n.From != builder.FromBinding || n.Registry != "http://anchor.mesh:3000/api/packages/novox/npm/" ||
+		n.Username != "anchor-agent" || n.Password != "bound-secret" {
+		t.Fatalf("the binding did not win over the genesis document: %+v", n)
+	}
+	if got := saysRegistry(n); !strings.Contains(got, "binding") {
+		t.Errorf("the log does not say the binding: %s", got)
+	}
+}
+
+func TestWithNeitherTheAgentHasNoRegistryAndSaysWhere(t *testing.T) {
+	registryFiles(t, "", "", "")
+	n, err := packagesFrom("workstation")
+	if err != nil {
+		t.Fatalf("an unbound optional requirement was a fault: %v", err)
+	}
+	if n.Enabled() || n.Machine != "workstation" {
+		t.Fatalf("a registry came from nowhere: %+v", n)
+	}
+	got := saysRegistry(n)
+	for _, want := range []string{"npm-package-registry", "unbound", "workstation"} {
+		if !strings.Contains(got, want) {
+			t.Errorf("the log does not say %q: %s", want, got)
+		}
+	}
+}
+
+func TestAGenesisDocumentMissingAFieldIsRefusedByName(t *testing.T) {
+	registryFiles(t, "", "", `{"at":"127.0.0.1","port":3000,"npm-path":"/api/packages/novox/npm/","as":"mesh-builder"}`)
+	if _, err := packagesFrom("anchor"); err == nil || !strings.Contains(err.Error(), "password") {
+		t.Fatalf("a genesis document with no password was taken: %v", err)
+	}
+}

cmd/mesh-builder/ready.go

@@ -0,0 +1,44 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+// **The build agent says it is ready** (novox/hq issue 544). It listens on nothing, so no http or tcp
+// check can see it work; it writes a mark once it is bound to its worker and pulls build work, and its
+// container's health check runs `mesh-builder ready`, which passes only while the mark is there. Without
+// it the node-engine could judge the agent only alive, and every walk that moved it waited out the whole
+// grace on each machine.
+//
+// The mark lives in the container's own temporary directory, never in the workspace the machine keeps:
+// a new container starts without it, and a restarted one removes it before it binds again.
+func readyMark() string { return filepath.Join(os.TempDir(), "mesh-builder.ready") }
+
+// notReady removes the mark: a holder starting is not taking work until it says so again.
+func notReady() error {
+	if err := os.Remove(readyMark()); err != nil && !errors.Is(err, os.ErrNotExist) {
+		return fmt.Errorf("cannot remove the mark that this agent takes build work (%s): %w", readyMark(), err)
+	}
+	return nil
+}
+
+// taking writes the mark. A mark that cannot be written is said, and the agent goes on building: its
+// check then says it is not ready, which is the truth the gate should hear.
+func taking(seat string) {
+	if err := os.WriteFile(readyMark(), []byte(seat+"\n"), 0o644); err != nil {
+		fmt.Fprintf(os.Stderr, "cannot mark that this agent takes build work (%s): %v\n", readyMark(), err)
+		return
+	}
+	fmt.Fprintf(os.Stderr, "taking build work from %s\n", seat)
+}
+
+// ready is the health check: nil when this container's agent is bound and pulling build work.
+func ready() error {
+	if _, err := os.Stat(readyMark()); err != nil {
+		return fmt.Errorf("not taking build work yet: %s is not there", readyMark())
+	}
+	return nil
+}

cmd/mesh-builder/ready_test.go

@@ -0,0 +1,32 @@
+package main
+
+import (
+	"os"
+	"testing"
+)
+
+// The health check passes only between the agent saying it takes work and its next start (novox/hq
+// issue 544).
+func TestTheAgentIsReadyOnlyOnceItTakesWork(t *testing.T) {
+	t.Setenv("TMPDIR", t.TempDir())
+	if err := ready(); err == nil {
+		t.Fatal("an agent that never took work is ready")
+	}
+	taking("mesh-build-machine")
+	if err := ready(); err != nil {
+		t.Fatalf("an agent taking work is not ready: %v", err)
+	}
+	// Started again, it is not ready until it binds again.
+	if err := notReady(); err != nil {
+		t.Fatal(err)
+	}
+	if err := ready(); err == nil {
+		t.Fatal("an agent starting again is ready before it takes work")
+	}
+	if err := notReady(); err != nil {
+		t.Fatalf("removing a mark that is not there failed: %v", err)
+	}
+	if _, err := os.Stat(readyMark()); err == nil {
+		t.Fatal("the mark is still there")
+	}
+}

cmd/mesh-builder/seat_test.go

@@ -0,0 +1,27 @@
+package main
+
+import (
+	"encoding/json"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// The seat a build machine serves comes from its credential (novox/hq ADR 0190 handover).
+func TestTheCredentialSaysWhichBuildRoleThisMachineServes(t *testing.T) {
+	var held Credential
+	if err := json.Unmarshal([]byte(`{"url":"nats://bus:4222","user":"anchor.builder","password":"x",
+		"claims":[{"seat":"mesh-build-machine","scope":"mesh","serves":[]}]}`), &held); err != nil {
+		t.Fatal(err)
+	}
+	if got := link.BuildSeatClaimed(held.seatsClaimed()); got != "mesh-build-machine" {
+		t.Errorf("the old builder's credential serves %q", got)
+	}
+	var bare Credential
+	if err := json.Unmarshal([]byte(`{"url":"nats://bus:4222","user":"anchor.build-agent","password":"x"}`), &bare); err != nil {
+		t.Fatal(err)
+	}
+	if got := link.BuildSeatClaimed(bare.seatsClaimed()); got != link.TheBuildMachine {
+		t.Errorf("a credential without claims serves %q, want %s", got, link.TheBuildMachine)
+	}
+}

cmd/mesh-builder/stdout_test.go

@@ -14,8 +14,9 @@ func TestBuilderDiagnosticsStayOffStdout(t *testing.T) {
 	allowed := map[string]bool{
 		"string(body)": true, // once.go: the result JSON, which IS stdout
 		"version)":     true, // --version
-		`"stopping")`: true,  // the loop.s shutdown line
-		"usage)":       true,  // --help text, for a human
+		`"stopping")`:  true, // the loop.s shutdown line
+		"usage)":       true, // --help text, for a human
+		"said)":        true, // busy: the answer its node-engine reads (novox/hq ADR 0335)
 	}
 	for _, file := range []string{"once.go", "main.go"} {
 		src, err := os.ReadFile(file)

cmd/mesh-builder/tried_test.go

@@ -0,0 +1,31 @@
+package main
+
+import (
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/builder"
+)
+
+// A try's outcome, as the build seat says it in the build's log (novox/hq issue 686): the repository's own
+// check's verdict, how long it took, and each line naming what failed.
+func TestATrysOutcomeNamesWhatFailed(t *testing.T) {
+	tried := triedOf(builder.CheckVerdict{Verdict: "pass", Summary: "the change touches no module", Took: 303 * time.Second,
+		Head: "c0ffee", Trunk: "ca3f43c", Gate: &builder.Layer{Verdict: "pass"},
+		Repo: &builder.Layer{Verdict: "fail", Summary: "its merge-check.sh failed: TestX",
+			Failed: "--- FAIL: TestX (0.01s)\n    x_test.go:12: got 1, want 2"}})
+	if tried.Verdict != "fail" || tried.Took != "5m3s" || len(tried.Failed) != 2 || tried.Trunk != "ca3f43c" ||
+		tried.Summary != "its merge-check.sh failed: TestX" {
+		t.Fatalf("a failed try: %+v", tried)
+	}
+	// A head that does not merge fails both layers: the check's own word.
+	conflict := triedOf(builder.CheckVerdict{Verdict: "fail", Summary: "does not merge", Gate: &builder.Layer{Verdict: "fail"},
+		Repo: &builder.Layer{Verdict: "fail", Summary: "does not merge"}})
+	if conflict.Verdict != "fail" || conflict.Summary != "does not merge" {
+		t.Fatalf("a try that does not merge: %+v", conflict)
+	}
+	// No verdict is an error, never a pass.
+	if none := triedOf(builder.CheckVerdict{}); none.Verdict != "error" {
+		t.Fatalf("a try with no verdict: %+v", none)
+	}
+}

cmd/mesh-builder/where_test.go

@@ -15,6 +15,8 @@ import (
 	"strings"
 	"testing"
 	"time"
+
+	"github.com/novox/mesh-controller/internal/broker"
 )
 
 // Where a builder publishes.
@@ -193,9 +195,9 @@ func TestThePinIsComparedInTheSpellingTheMeshWritesIt(t *testing.T) {
 	}
 }
 
-// handshakeWith runs the builder's own pin check against an address.
+// handshakeWith runs the pin check the builder dials with against an address.
 func handshakeWith(address, pin string) error {
-	conn, err := tls.Dial("tcp", address, pinning(pin))
+	conn, err := tls.Dial("tcp", address, broker.PinnedToFingerprint(pin))
 	if err != nil {
 		return err
 	}

cmd/mesh-controller/accept_outside.go

@@ -0,0 +1,145 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"sort"
+	"strings"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// A provision whose credential only a person outside the mesh can give (novox/hq ADR 0337, issue 164, issue 165):
+// given once for its provider, at the controller's terminal, and sealed in one act to every consumer that binds the
+// provision from that provider now. The value is never read back, printed or kept.
+
+// outsideOffer is the provider module's own name when `secret accept <node> <module> <name>` names a provision that
+// module offers with a credential issued outside the mesh, and "" when it names anything else (an own secret, or a
+// pair with --provider).
+func outsideOffer(ctx context.Context, module, name, provider string) (string, error) {
+	if provider != "" {
+		return "", nil
+	}
+	open, err := openStores(ctx)
+	if err != nil {
+		return "", err
+	}
+	defer open.Close()
+	shelf, err := open.inventory.Catalogue(ctx)
+	if err != nil {
+		return "", err
+	}
+	if m, known := shelf[module]; known && m.IssuedOutsideOf(name) {
+		return module, nil
+	}
+	return "", nil
+}
+
+// offeredOutsideBy is a module that offers the provision with a credential issued outside the mesh, or "".
+func offeredOutsideBy(ctx context.Context, provision string) (string, error) {
+	open, err := openStores(ctx)
+	if err != nil {
+		return "", err
+	}
+	defer open.Close()
+	shelf, err := open.inventory.Catalogue(ctx)
+	if err != nil {
+		return "", err
+	}
+	module, _ := catalogue.OffersIssuedOutside(shelf, provision)
+	return module, nil
+}
+
+// consumersFrom is every consumer that binds a provision from one provider now, found by resolving every machine as
+// its next send would, and the machines that could not be resolved, with why.
+func consumersFrom(ctx context.Context, open *stores, provider, providerModule, provision string) (
+	[]inventory.PairEnd, []string, error) {
+	nodes, err := open.inventory.Nodes(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+	var out []inventory.PairEnd
+	var unresolved []string
+	for _, n := range nodes {
+		plan, _, err := planFor(ctx, open, n.Name)
+		if err != nil {
+			unresolved = append(unresolved, fmt.Sprintf("%s: %s", n.Name, oneLine(err.Error())))
+			continue
+		}
+		out = append(out, bindsFrom(plan, n.Name, provider, providerModule, provision)...)
+	}
+	return out, unresolved, nil
+}
+
+// bindsFrom is every consumer on one machine whose resolution answers the provision from that provider. Pure.
+func bindsFrom(plan catalogue.Resolution, machine, provider, providerModule, provision string) []inventory.PairEnd {
+	var out []inventory.PairEnd
+	for _, need := range plan.Needs {
+		if need.ByRecord || need.Name != provision || need.From != provider {
+			continue
+		}
+		if need.Module != "" && need.Module != providerModule {
+			continue
+		}
+		out = append(out, inventory.PairEnd{Consumer: machine, ConsumerModule: need.For, Local: need.Local})
+	}
+	sort.Slice(out, func(i, j int) bool {
+		return out[i].ConsumerModule+"\x00"+out[i].Local < out[j].ConsumerModule+"\x00"+out[j].Local
+	})
+	return out
+}
+
+// acceptForProvision gives a provision's credential issued outside the mesh, once for its provider (ADR 0337 §3).
+func acceptForProvision(ctx context.Context, provider, providerModule, provision, value string) error {
+	open, err := openStores(ctx)
+	if err != nil {
+		return err
+	}
+	defer open.Close()
+	consumers, unresolved, err := consumersFrom(ctx, open, provider, providerModule, provision)
+	if err != nil {
+		return err
+	}
+	accepted, err := open.inventory.AcceptSecretForProvision(ctx, provision, provider, providerModule, value, consumers)
+	value = ""
+	if err != nil {
+		return err
+	}
+	fmt.Print(acceptedSaid(provider, providerModule, provision, accepted, unresolved))
+	if len(accepted.Sealed) == 0 {
+		return nil
+	}
+	if err := sendTo(ctx, open, accepted.Machines); err != nil {
+		return fmt.Errorf("%s is sealed and could not be sent: %w; `push %s` sends it", provision, err,
+			strings.Join(accepted.Machines, "`, `push "))
+	}
+	fmt.Printf("  sent %s; each consumer starts again on it\n", strings.Join(accepted.Machines, ", "))
+	return nil
+}
+
+// acceptedSaid is what one accept for a provider did, in words that never carry the value. Pure.
+func acceptedSaid(provider, providerModule, provision string, a inventory.ProvisionAccepted, unresolved []string) string {
+	var b strings.Builder
+	if len(a.Sealed) == 0 {
+		fmt.Fprintf(&b, "%s from %s on %s: no consumer binds it now, so nothing was sealed; a consumer that binds "+
+			"later waits for it, and this line given again seals it to every consumer then\n", provision,
+			providerModule, provider)
+	} else {
+		var names []string
+		for _, c := range a.Sealed {
+			names = append(names, fmt.Sprintf("%s on %s%s", c.ConsumerModule, c.Consumer, asLocal(c.Local)))
+		}
+		fmt.Fprintf(&b, "%s from %s on %s is given, sealed to %s and to %s\n", provision, providerModule, provider,
+			strings.Join(names, ", "), provider)
+		fmt.Fprintf(&b, "  the mesh cannot read it back, never makes one of its own for it, and will not rotate it\n")
+	}
+	for _, c := range a.Unsealable {
+		fmt.Fprintf(&b, "  not sealed to %s on %s: no sealing key on that machine; give it again once it has one\n",
+			c.ConsumerModule, c.Consumer)
+	}
+	for _, u := range unresolved {
+		fmt.Fprintf(&b, "  not known whether a consumer on %s binds it, which did not resolve; give it again once it does\n", u)
+	}
+	return b.String()
+}

cmd/mesh-controller/acting.go

@@ -0,0 +1,378 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"os"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/nats-io/nats.go"
+	"github.com/nats-io/nats.go/jetstream"
+
+	"github.com/novox/mesh-controller/internal/broker"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/lease"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// Acting under the lease (novox/hq to-be 45 §6, ADR 0227 rule 1).
+//
+// **Only the instance holding the lease acts**: sends a declaration, writes a plan, a condition or a
+// call. Every one of those passes theLease.epoch, which answers the epoch the act carries or why it may
+// not happen. Three ways a process stands to the lease:
+//
+//   - **The serving controller** takes it before it does anything else — before it asserts the bus's
+//     objects, which are the controller's to write — waiting while another holds it, and renews it.
+//     Another holder seen, or the key's age passed with no renewal made, is the lease lost: the gate
+//     closes at once and the process exits, so its service manager restarts it as a candidate (serve,
+//     in push.go). A renewal the bus does not answer in time is not a loss (novox/hq issue 477): the
+//     lease is kept, no new act starts once half the key's age passed unrenewed, and the next renewal
+//     made opens the gate again.
+//   - **A command run at a shell** — `push` in the installer, the lab, a person repairing a mesh whose
+//     controller is down (issue 201) — acts **under the holder's epoch** when a controller holds the
+//     lease: it is the same mesh's word, composed and sent under the store's hold of each machine like
+//     the serving controller's, and the epoch it carries is read at the moment it acts, so a handover
+//     between makes it stale and refused like any other. **When nobody holds the lease, the command
+//     takes it** for as long as it runs and gives it back; a controller starting meanwhile waits for
+//     it, as it would for another controller.
+//   - **A process with no bus** — a test, a command that only reads — acts with no epoch and is
+//     refused nothing: there is nothing to order against, and nothing it does reaches a machine.
+//
+// **Unleased, said and temporary.** A serving controller whose bus refuses it the lease's key — the bus's
+// user list is older than this build and does not grant the bucket yet — and that sees no other holder
+// serves without one, as every controller did before the lease: declarations carry no epoch, which no
+// node-engine refuses. Said once, kept as a condition (S12), and tried again every renewal interval; the
+// first push that sends the bus its new user list grants it, and the next try takes it. Refusing to act
+// instead would be a controller that can never send the user list that lets it act.
+
+// actor is this process's standing to the lease.
+type actor struct {
+	mu sync.Mutex
+	// held is the lease this process holds: the serving controller's, or a command's own.
+	held *lease.Lease
+	// unleased is why a serving controller acts without the lease; empty while it holds it or is not
+	// serving.
+	unleased string
+	// serving is a serving controller, which never borrows another's epoch.
+	serving bool
+	// kv is the lease bucket, for a command to read the holder's epoch from.
+	kv    jetstream.KeyValue
+	close func()
+	// noBus is a process with no bus configured.
+	noBus bool
+	// reset is when the lease bucket was found raised again from nothing and its revisions moved past
+	// the highest epoch issued, and what was said of it; zero when it was not (S12).
+	reset     time.Time
+	resetSaid string
+	// renewEvery and poll, when set, are how often the serving controller renews the lease it holds and
+	// looks again at one another holds, in place of the lease's own: a test's, so two controllers hand the
+	// lease over in a second rather than in a renewal of five (novox/hq issue 591). A renewal is given
+	// the lease's own RenewEvery to answer however often it is made, so a slow bus does not lose it.
+	renewEvery, poll time.Duration
+}
+
+// theLease is this process's standing to the lease.
+var theLease = &actor{}
+
+// instance names this process among controller instances: its machine, its process and when it
+// started. The lease's holder and every call this process keeps carry it.
+var instance = func() string {
+	host, _ := os.Hostname()
+	return fmt.Sprintf("controller@%s pid %d since %s", host, os.Getpid(), time.Now().UTC().Format(time.RFC3339))
+}()
+
+// epoch is the gate: the epoch an act carries — zero for none — or why it may not happen.
+func (a *actor) epoch(ctx context.Context) (uint64, error) {
+	a.mu.Lock()
+	held, serving, unleased, noBus := a.held, a.serving, a.unleased, a.noBus
+	a.mu.Unlock()
+	switch {
+	case held != nil:
+		return held.Epoch()
+	case serving && unleased != "":
+		return 0, nil
+	case serving:
+		return 0, lease.ErrNotHeld
+	case noBus:
+		return 0, nil
+	}
+	return a.forACommand(ctx)
+}
+
+// forACommand is a command's epoch: the holder's, or a lease of its own when nobody holds one.
+func (a *actor) forACommand(ctx context.Context) (uint64, error) {
+	a.mu.Lock()
+	defer a.mu.Unlock()
+	if a.held != nil {
+		return a.held.Epoch()
+	}
+	if a.kv == nil {
+		address, err := broker.BusAddress()
+		if err != nil {
+			// No bus: this process reaches no machine, and has nothing to order against.
+			a.noBus = true
+			return 0, nil
+		}
+		js, err := broker.Dial(address)
+		if err != nil {
+			return 0, fmt.Errorf("the bus cannot be reached, so whether a controller holds the lease cannot be "+
+				"read and nothing is done: %w", err)
+		}
+		api, err := jetstream.New(js.Conn())
+		if err != nil {
+			js.Close()
+			return 0, err
+		}
+		reading, cancel := context.WithTimeout(ctx, 10*time.Second)
+		defer cancel()
+		if err := broker.EnsureLeaseBucket(reading, api); err != nil {
+			js.Close()
+			return 0, err
+		}
+		kv, err := api.KeyValue(reading, broker.LeaseBucket)
+		if err != nil {
+			js.Close()
+			return 0, err
+		}
+		a.kv, a.close = kv, js.Close
+		if _, found, err := lease.Current(reading, kv); err == nil && !found {
+			// Nobody: this command takes it for as long as it runs.
+			l, err := lease.Open(reading, api, broker.LeaseBucket, lease.Options{Holder: holderOf(instance),
+				Say: func(format string, args ...any) { fmt.Printf(format+"\n", args...) }})
+			if err != nil {
+				return 0, err
+			}
+			epoch, err := l.TryTake(reading)
+			if err != nil {
+				return 0, fmt.Errorf("no controller holds the lease and this command could not take it: %w", err)
+			}
+			keeping, stop := context.WithCancel(context.Background())
+			go l.Keep(keeping)
+			a.held = l
+			closeBus := a.close
+			a.close = func() {
+				stop()
+				l.Release(context.Background())
+				closeBus()
+			}
+			return epoch, nil
+		}
+	}
+	reading, cancel := context.WithTimeout(ctx, 10*time.Second)
+	defer cancel()
+	holder, found, err := lease.Current(reading, a.kv)
+	if err != nil {
+		return 0, fmt.Errorf("who holds the controller lease cannot be read, so nothing is done: %w", err)
+	}
+	if !found {
+		return 0, errors.New("the controller that held the lease while this command ran let go of it; nothing " +
+			"more is done under an epoch nobody holds — run the command again")
+	}
+	return holder.Epoch, nil
+}
+
+// release gives back what this process holds, at its end.
+func (a *actor) release() {
+	a.mu.Lock()
+	closing := a.close
+	a.close = nil
+	a.mu.Unlock()
+	if closing != nil {
+		closing()
+	}
+}
+
+// holderOf is this process as the lease's holder.
+func holderOf(instance string) lease.Holder {
+	host, _ := os.Hostname()
+	build := runningBuild()
+	if build == "" {
+		build = version
+	}
+	return lease.Holder{Instance: instance, Host: host, Build: build}
+}
+
+// RunningBuildVar is where the declaration tells this process which build it is (module.json, the
+// controller process's env): the version its bundle is delivered as, `${version}` composed by the
+// catalogue from the bundle's digest. Empty for a process placed by hand.
+const RunningBuildVar = "MESH_CONTROLLER_VERSION"
+
+// runningBuild is the version of the build this process is, or empty when the declaration did not say.
+func runningBuild() string {
+	return strings.TrimSpace(os.Getenv(RunningBuildVar))
+}
+
+// serveUnderTheLease takes the lease for the serving controller, waiting while another holds it, and
+// keeps it until ctx ends. Lost is closed when it is lost; the caller exits on it.
+func (a *actor) serveUnderTheLease(ctx context.Context, inv *inventory.Inventory, address string) (lost <-chan struct{}, err error) {
+	a.mu.Lock()
+	a.serving = true
+	a.mu.Unlock()
+	// Its own connection, held as long as the lease, and named so (novox/hq issue 327).
+	js, err := broker.Dial(address, nats.Name(broker.ConnectionName+" lease"))
+	if err != nil {
+		return nil, fmt.Errorf("the mesh is on the bus at %s and this control plane cannot reach it to take the "+
+			"lease: %w", broker.BareAddress(address), err)
+	}
+	api, err := jetstream.New(js.Conn())
+	if err != nil {
+		js.Close()
+		return nil, err
+	}
+	asserting, cancel := context.WithTimeout(ctx, 10*time.Second)
+	err = broker.EnsureLeaseBucket(asserting, api)
+	cancel()
+	if err != nil {
+		js.Close()
+		return nil, err
+	}
+	say := func(format string, args ...any) { fmt.Printf(format+"\n", args...) }
+	l, err := lease.Open(ctx, api, broker.LeaseBucket, lease.Options{Holder: holderOf(instance),
+		RenewEvery: a.renewEvery, RenewWithin: lease.RenewEvery, Poll: a.poll, Floor: inv.HighestEpoch, Say: say, Health: controllerHealth, Moved: func(was, floor uint64) {
+			a.mu.Lock()
+			defer a.mu.Unlock()
+			a.reset = time.Now()
+			a.resetSaid = fmt.Sprintf("the lease bucket was at revision %d with epoch %d already issued: it was "+
+				"raised again from nothing (a bus whose data was replaced), and its revisions were moved past %d so "+
+				"no machine refuses the next epoch", was, floor, floor)
+		}})
+	if err != nil {
+		js.Close()
+		return nil, err
+	}
+	gone := make(chan struct{})
+	epoch, err := l.Take(ctx)
+	switch {
+	case ctx.Err() != nil:
+		js.Close()
+		return nil, ctx.Err()
+	case err != nil && !errors.Is(err, lease.ErrUnwritable):
+		// Whether another controller acts cannot be told: this one does not act, and exits to try again.
+		js.Close()
+		return nil, err
+	case err != nil:
+		// Nobody holds it and the bus will not let it be written: unleased, said, tried again (see above).
+		a.mu.Lock()
+		a.unleased = err.Error()
+		a.mu.Unlock()
+		say("this controller serves WITHOUT the lease: %v. Its declarations carry no epoch; it tries again "+
+			"every %s, and the first push that sends the bus its user list grants it", err, lease.RenewEvery)
+		go a.takeWhenGranted(ctx, l, inv, gone)
+	default:
+		a.took(ctx, l, inv, epoch, gone)
+	}
+	a.mu.Lock()
+	a.close = func() {
+		if held, err := l.Epoch(); err == nil {
+			ending, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+			if err := inv.EndEpoch(ending, held, inventory.EpochReleased); err != nil {
+				say("how epoch %d ended could not be recorded: %v", held, err)
+			}
+			cancel()
+		}
+		l.Release(context.Background())
+		js.Close()
+	}
+	a.mu.Unlock()
+	return gone, nil
+}
+
+// took is the lease taken: recorded, earlier epochs nobody gave back ended as expired, kept.
+func (a *actor) took(ctx context.Context, l *lease.Lease, inv *inventory.Inventory, epoch uint64, gone chan struct{}) {
+	a.mu.Lock()
+	a.held, a.unleased = l, ""
+	a.mu.Unlock()
+	h := holderOf(instance)
+	recording, cancel := context.WithTimeout(ctx, 10*time.Second)
+	expired, err := inv.TookEpoch(recording, inventory.Epoch{Epoch: epoch, Instance: h.Instance, Host: h.Host,
+		Build: h.Build, Taken: time.Now()})
+	cancel()
+	if err != nil {
+		fmt.Printf("epoch %d could not be recorded as taken, so a stale refusal from it will not name it: %v\n", epoch, err)
+	}
+	for _, e := range expired {
+		fmt.Printf("the controller of epoch %d (%s) stopped renewing the lease without giving it back: it is "+
+			"taken over at epoch %d\n", e.Epoch, e.Instance, epoch)
+	}
+	go l.Keep(ctx)
+	go func() {
+		<-l.Lost()
+		if ctx.Err() == nil {
+			why := l.LostWhy()
+			ending, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+			_ = inv.EndEpoch(ending, epoch, inventory.EpochLost)
+			cancel()
+			fmt.Printf("the controller lease was lost (epoch %d): %v — this controller stops and exits, to "+
+				"be started again as a candidate\n", epoch, why)
+		}
+		close(gone)
+	}()
+}
+
+// takeWhenGranted tries the lease again every renewal interval while serving unleased, and stops this
+// controller if another took it meanwhile: two serving at once is what the lease is for.
+func (a *actor) takeWhenGranted(ctx context.Context, l *lease.Lease, inv *inventory.Inventory, gone chan struct{}) {
+	tick := time.NewTicker(lease.RenewEvery)
+	defer tick.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-tick.C:
+		}
+		epoch, err := l.TryTake(ctx)
+		if errors.Is(err, lease.ErrTaken) {
+			fmt.Printf("another controller took the lease while this one served without it: %v — this one "+
+				"stops and exits\n", err)
+			close(gone)
+			return
+		}
+		if err != nil {
+			// Still not written, or not readable this time: unleased, said by S12, tried again.
+			a.mu.Lock()
+			a.unleased = err.Error()
+			a.mu.Unlock()
+			continue
+		}
+		a.took(ctx, l, inv, epoch, gone)
+		return
+	}
+}
+
+// standing is what `status` and the self-check say of this process and the lease.
+type standing struct {
+	Epoch    uint64
+	Held     bool
+	Renewed  time.Time
+	Unleased string
+	// Reset is when the lease bucket was found raised again from nothing, and ResetSaid what of it.
+	Reset     time.Time
+	ResetSaid string
+}
+
+func (a *actor) standing() standing {
+	a.mu.Lock()
+	held, unleased, reset, resetSaid := a.held, a.unleased, a.reset, a.resetSaid
+	a.mu.Unlock()
+	st := standing{Unleased: unleased, Reset: reset, ResetSaid: resetSaid}
+	if held == nil {
+		return st
+	}
+	epoch, err := held.Epoch()
+	st.Epoch, st.Held, st.Renewed = epoch, err == nil, held.Renewed()
+	return st
+}
+
+// The gates, given to what acts: a declaration's send (link) and a plan's write (the inventory).
+func init() {
+	link.ActingGate = func(ctx context.Context) error {
+		_, err := theLease.epoch(ctx)
+		if err != nil {
+			return fmt.Errorf("this controller may not send: %w", err)
+		}
+		return nil
+	}
+}

cmd/mesh-controller/acts.go

@@ -3,10 +3,15 @@ package main
 import (
 	"context"
 	"fmt"
+	"github.com/novox/mesh-controller/internal/broker"
+	"io"
+	"slices"
 	"sort"
 	"strings"
+	"time"
 
 	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
 )
 
 // The things the mesh can be asked to do, separated from how it was asked.
@@ -38,44 +43,305 @@ import (
 //
 // It costs a resolution per machine. Assignment is a person typing a command, and being told which
 // machines this just blocked is worth more than the milliseconds.
-func assign(ctx context.Context, open *stores, node, module string) (string, error) {
-	if err := open.inventory.Assign(ctx, node, module); err != nil {
+func assign(ctx context.Context, open *stores, node string, modules ...string) (string, error) {
+	return assignWith(ctx, open, node, assignOptions{}, modules...)
+}
+
+// assignWith is assign asked with its options: build, for a module known and not built (novox/hq issue 325).
+func assignWith(ctx context.Context, open *stores, node string, opts assignOptions, modules ...string) (string, error) {
+	if len(modules) == 0 {
+		return "", fmt.Errorf("assign %s names no module", node)
+	}
+	if err := refusedMovingTheController(modules); err != nil {
 		return "", err
 	}
-	said := fmt.Sprintf("%s is assigned %s", node, module)
-	plan, _, err := planFor(ctx, open, node)
+	// Every line of the answer comes from the one resolution after the write (novox/hq issue 237):
+	// what the reads before it would say about a machine left out is not the answer's.
+	ctx = leftOutSaidBy(ctx, io.Discard)
+	// Held while it is recorded, so it cannot land between a converge's preview and its flip and
+	// be taken without ever having been previewed (novox/hq ADR 0100).
+	ctx, release, err := holdNodes(ctx, open, []string{node})
+	if err != nil {
+		return "", err
+	}
+	defer release()
+	// **A module the catalogue does not hold is looked for further before it is refused** (novox/hq issue
+	// 325): a build in flight keeps the assignment pending, a module known and not built is said with how to
+	// build it, and only a name the mesh never heard of is refused as unknown. Several modules in one act
+	// are judged together (ADR 0207), so an act naming one not registered is not made in part.
+	if missing, err := notInCatalogue(ctx, open, modules); err != nil {
+		return "", err
+	} else if len(missing) > 0 {
+		if len(modules) == 1 {
+			return notRegistered(ctx, open, node, modules[0], opts)
+		}
+		var lines []string
+		for _, m := range missing {
+			where, err := whereIs(ctx, open.inventory, m, time.Now())
+			if err != nil {
+				return "", err
+			}
+			lines = append(lines, where.said)
+		}
+		return "", fmt.Errorf("%w: nothing was assigned, since modules assigned together are judged together "+
+			"(ADR 0207) and %s not registered:\n  %s\n  assign them together once each is registered, or each "+
+			"alone to keep it pending on its build", inventory.ErrNoSuchModule, strings.Join(missing, ", "),
+			strings.Join(lines, "\n  "))
+	}
+	// **The one assignment refused for what the node lacks** (novox/hq ADR 0207). Everything else
+	// an assignment leaves unresolved is kept, because assignment is not an ordering; a module whose
+	// resources are applied through a seat nothing on the node holds is refused, because that order
+	// — the service manager, the package manager and the runtime before anything that installs,
+	// runs or contains — is the mesh's to keep. Several modules in one act are judged together, so
+	// holders that depend on each other go on in one command.
+	shelf, before, err := seatDependenciesOnAssign(ctx, open, node, modules)
+	if err != nil {
+		return "", err
+	}
+	// **Before the new assignment can unsettle a seat somebody holds only by being alone**
+	// (novox/hq 04-ISSUES/170): what the mesh derived so far is written down, and then the
+	// assignment resolves against a record rather than against a coincidence.
+	settled, err := recordDerivedHolders(ctx, open)
+	if err != nil {
+		return "", err
+	}
+	var lines []string
+	var added []string
+	for _, module := range modules {
+		fresh, err := open.inventory.Assign(ctx, node, module)
+		if err != nil {
+			return strings.Join(lines, "\n"), err
+		}
+		if !fresh {
+			// Nothing changed, and saying "is assigned" would read as an action. One node runs one
+			// of each — the module's name is the assignment's identity (novox/hq ADR 0115).
+			lines = append(lines, fmt.Sprintf(
+				"%s already runs %s — one node runs one of each (ADR 0115); nothing changed", node, module))
+			continue
+		}
+		added = append(added, module)
+		lines = append(lines, fmt.Sprintf("%s is assigned %s", node, module))
+	}
+	if len(added) == 0 {
+		return strings.Join(lines, "\n"), nil
+	}
+	answer := strings.Join(lines, "\n")
+	for _, line := range settled {
+		answer += "\n  " + line
+	}
+	// Its bus credential, in the same act (novox/hq issue 203): an assignment pushed before its
+	// credential exists delivers a process that cannot authenticate and crash-loops until somebody
+	// runs a second verb and a second push. Issued here when the module speaks on the bus and has
+	// no credential yet; kept when it has one, so re-assigning rotates nothing.
+	var issued []string
+	for _, module := range added {
+		if line := issueOnAssign(ctx, open, node, module); line != "" {
+			issued = append(issued, line)
+		}
+	}
+	// **The one resolution the rest of the answer is said from** (novox/hq issue 237), taken after
+	// the write: what this act changed about this node's unmet seat dependencies, and nothing else
+	// (novox/hq ADR 0207) — a dependency of a module just assigned, or one this assignment met; the
+	// rest of the node's list, and every other node's, is `status`'s — and whether the node resolves.
+	after := resolvedAfter(ctx, open, shelf, node)
+	for _, line := range unheldChangeTo(shelf, node, before, after.modules, after.unheld) {
+		answer += "\n  " + line
+	}
+	for _, line := range issued {
+		answer += "\n  " + line
+	}
+	plan, err := after.plan, after.err
 	if err != nil {
 		// Kept, and still refused. Both halves are the answer, and the rest of the mesh is still
 		// worth reporting: this machine's refusal is rarely the only consequence.
-		return said + blockedElsewhere(ctx, open, node), err
+		return answer + blockedElsewhere(ctx, open, node), err
 	}
 	// Kept, and cannot be hosted here. Said at once rather than discovered at push: a module whose
 	// capability the machine lacks is on the wrong machine, and the assignment records what a person
 	// meant while this line says it will not run until it moves. The rest of the node still pushes.
+	isAdded := map[string]bool{}
+	for _, m := range added {
+		isAdded[m] = true
+	}
 	for _, u := range plan.Unhostable {
-		if u.Module != module {
+		if !isAdded[u.Module] {
 			continue
 		}
 		for _, c := range u.Missing {
-			said += "\n  but " + catalogue.WrongMachine(u.Module, c, node)
+			answer += "\n  but " + catalogue.WrongMachine(u.Module, c, node)
 		}
 	}
-	return said + fmt.Sprintf("\n  run `push %s` to send it", node) +
+	return answer + fmt.Sprintf("\n  run `push %s` to send it", node) +
 		blockedElsewhere(ctx, open, node), nil
 }
 
-// unassign takes a module off a node. What it leaves behind is the host's business: a directory
+// seatDependenciesOnAssign is the refusal ADR 0207 makes at assignment, or nothing, with the
+// catalogue and the node's assignments it was judged against. Modules already assigned are not new
+// and are not judged again.
+func seatDependenciesOnAssign(ctx context.Context, open *stores, node string, modules []string) (
+	map[string]catalogue.Manifest, []string, error) {
+	shelf, err := open.inventory.Catalogue(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+	assigned, err := open.inventory.Assigned(ctx, node)
+	if err != nil {
+		return nil, nil, err
+	}
+	already := map[string]bool{}
+	for _, a := range assigned {
+		already[a] = true
+	}
+	var adding []string
+	for _, m := range modules {
+		if !already[m] {
+			adding = append(adding, m)
+		}
+	}
+	// The lines AssignRefusal says beside an assignment it lets through are said by unheldChange
+	// with everything else this act changed, so they are not said twice.
+	if _, err := catalogue.AssignRefusal(shelf, node, assigned, adding); err != nil {
+		return nil, nil, err
+	}
+	// Two modules declaring one path or unit, or one package present and absent, is refused before anything
+	// is recorded (novox/hq ADR 0210, ADR 0303, 04-ISSUES/235): kept, the node would not resolve until one came
+	// off again. Two modules declaring one package present is not a collision (ADR 0303, issue 628).
+	if err := catalogue.CollisionRefusal(shelf, node, assigned, adding); err != nil {
+		return nil, nil, err
+	}
+	return shelf, assigned, nil
+}
+
+// unassign takes modules off a node. What they leave behind is the host's business: a directory
 // holding anything the mesh did not put there is kept (novox/hq ADR 0030).
 //
 // It reports the rest of the mesh for the same reason assign does, and more sharply: taking a
 // module off one machine is the ordinary way to stop providing something to another, and nothing
 // about the command's own output would ever have said so.
-func unassign(ctx context.Context, open *stores, node, module string) (string, error) {
-	if err := open.inventory.Unassign(ctx, node, module); err != nil {
+//
+// **Refused when it takes away the last holder of a seat a module left on the node depends on**
+// (novox/hq ADR 0207) — the other side of refusing that module's assignment without one. Several
+// modules in one act are judged together, so a holder and its dependents come off in one command.
+func unassign(ctx context.Context, open *stores, node string, modules ...string) (string, error) {
+	if err := refusedMovingTheController(modules); err != nil {
 		return "", err
 	}
-	return fmt.Sprintf("%s no longer runs %s — run `push %s` to make it so",
-		node, module, node) + blockedElsewhere(ctx, open, node), nil
+	if len(modules) == 0 {
+		return "", fmt.Errorf("unassign %s names no module", node)
+	}
+	// One resolution after the write, as assign's answer (novox/hq issue 237).
+	ctx = leftOutSaidBy(ctx, io.Discard)
+	ctx, release, err := holdNodes(ctx, open, []string{node})
+	if err != nil {
+		return "", err
+	}
+	defer release()
+	shelf, err := open.inventory.Catalogue(ctx)
+	if err != nil {
+		return "", err
+	}
+	assigned, err := open.inventory.Assigned(ctx, node)
+	if err != nil {
+		return "", err
+	}
+	// Every one checked before any is taken off, so a refusal leaves the node as it was.
+	runs := map[string]bool{}
+	for _, a := range assigned {
+		runs[a] = true
+	}
+	// A module only pending on the node (novox/hq issue 325) is withdrawn, when it is the act's one module:
+	// that is the undo of an assignment kept while its build runs.
+	if len(modules) == 1 && !runs[modules[0]] {
+		said, withdrawn, err := withdrawPending(ctx, open.inventory, node, modules[0])
+		if err != nil {
+			return "", err
+		}
+		if withdrawn {
+			return said, nil
+		}
+	}
+	for _, module := range modules {
+		if !runs[module] {
+			return "", fmt.Errorf("%s is not assigned to %s", module, node)
+		}
+	}
+	if err := catalogue.UnassignRefusal(shelf, node, assigned, modules); err != nil {
+		return "", err
+	}
+	for _, module := range modules {
+		if err := open.inventory.Unassign(ctx, node, module); err != nil {
+			return "", err
+		}
+	}
+	answer := fmt.Sprintf("%s no longer runs %s — run `push %s` to make it so",
+		node, strings.Join(modules, ", "), node)
+	after := resolvedAfter(ctx, open, shelf, node)
+	for _, line := range unheldChangeTo(shelf, node, assigned, after.modules, after.unheld) {
+		answer += "\n  " + line
+	}
+	// Whether the node itself still resolves, from the same resolution: before, only the rest of the
+	// mesh's reads said it, on standard error and once per other machine.
+	if after.err != nil {
+		if unresolvable(after.err) {
+			answer += fmt.Sprintf("\n  but %s does not resolve now, so nothing will be sent to it:", node)
+		} else {
+			answer += fmt.Sprintf("\n  but whether %s still resolves could not be read:", node)
+		}
+		for _, line := range strings.Split(strings.TrimRight(after.err.Error(), "\n"), "\n") {
+			answer += "\n    " + strings.TrimSpace(line)
+		}
+	}
+	// What it leaves behind that is irreplaceable is kept and retired, never removed (novox/hq ADR 0233).
+	for _, line := range keptOnUnassign(ctx, open.inventory, node, modules) {
+		answer += "\n  " + line
+	}
+	return answer + blockedElsewhere(ctx, open, node), nil
+}
+
+// afterAct is the one resolution of a node an act's answer is said from, taken after its write
+// (novox/hq issue 237): the plan or why there is none, the modules it has on the node, and its unmet
+// seat dependencies.
+type afterAct struct {
+	plan    catalogue.Resolution
+	err     error
+	modules []string
+	unheld  []catalogue.Unheld
+}
+
+// resolvedAfter resolves the node as `plan` does, once, after the act's write. When the node resolves,
+// its modules and unmet seat dependencies are the resolution's — the closure, so a holder pulled in by
+// a requirement counts as `plan` counts it. When it does not, they are judged over the assignments read
+// after the write, which can only find more unmet than the closure would: a seat said held there is
+// held in the closure too.
+func resolvedAfter(ctx context.Context, open *stores, shelf map[string]catalogue.Manifest, node string) afterAct {
+	plan, _, err := planFor(ctx, open, node)
+	if err == nil {
+		out := afterAct{plan: plan, unheld: plan.Unheld}
+		for _, m := range plan.Modules {
+			out.modules = append(out.modules, m.Module)
+		}
+		return out
+	}
+	out := afterAct{err: err}
+	assigned, readErr := open.inventory.Assigned(ctx, node)
+	if readErr != nil {
+		return out
+	}
+	out.modules, out.unheld = assigned, unheldOver(shelf, node, assigned)
+	return out
+}
+
+// splitModules is a surface's one `module` field as the modules it names: several, comma-separated,
+// are one act (novox/hq ADR 0207), so the holders that depend on each other go on together from the
+// command API and the controller seat's verbs as they do from the command line.
+func splitModules(field string) []string {
+	var out []string
+	for _, m := range strings.Split(field, ",") {
+		if m = strings.TrimSpace(m); m != "" {
+			out = append(out, m)
+		}
+	}
+	return out
 }
 
 // blockedElsewhere is every OTHER machine that cannot be worked out as things now stand.
@@ -123,3 +389,51 @@ func blockedElsewhere(ctx context.Context, open *stores, except string) string {
 	out.WriteString("\nThis may or may not be what just changed — it is what is true now.")
 	return out.String()
 }
+
+// issueOnAssign gives a newly assigned module its bus credential, the way `module issue` does, and
+// says what it did in one line. Nothing for a module that declares no broker secret and runs no
+// provisioner client; nothing for one whose user is already minted (a credential is rotated on
+// purpose, never by re-assigning); and when the bus cannot be reached from here, the line names the
+// verb and the push that would refuse the module until it is run — never a silent placeholder (novox/hq issue 203).
+func issueOnAssign(ctx context.Context, open *stores, node, module string) string {
+	inv := open.inventory
+	shelf, err := inv.Catalogue(ctx)
+	if err != nil {
+		return ""
+	}
+	m, known := shelf[module]
+	if !known || mayIssue(m) != nil {
+		return ""
+	}
+	user := broker.Principal{Kind: broker.KindModule, Node: node, Module: module}.Username()
+	if _, reads := m.OwnSecrets["broker"]; !reads {
+		// A module running the provisioner client alone is minted the client's account (issue 917).
+		user = broker.Principal{Kind: broker.KindProvisioner, Node: node, Module: module}.Username()
+	}
+	if _, minted, err := inv.BusUserHash(ctx, user); err != nil || minted {
+		return ""
+	}
+	busAddress, err := broker.BusAddress()
+	if err == nil {
+		err = issueOnTheNewBus(ctx, inv, m, node, busAddress)
+	}
+	if err != nil {
+		return fmt.Sprintf("its bus credential is not issued (%v): `module issue %s --node %s` first — "+
+			"`push %s` refuses to send %s until it is", err, module, node, node, module)
+	}
+	return fmt.Sprintf("its bus credential is issued and sealed to %s, and arrives with the push", node)
+}
+
+// refusedMovingTheController refuses assigning or unassigning the controller's module through a verb (review of
+// novox/hq ADR 0272): the node it is assigned to is the control-node, and the control-node's operator account is
+// the controller's terminal, so whoever moves the module chooses the terminal. At the terminal alone, as every
+// change that says who may change what.
+func refusedMovingTheController(modules []string) error {
+	verb, through := throughAVerb()
+	if !through || !slices.Contains(modules, controllerModule) {
+		return nil
+	}
+	return fmt.Errorf("%s is assigned and unassigned at the controller's terminal only (mesh-cli on the control-node), "+
+		"never through a verb (this came through %q): the node it runs on is the control-node, whose operator is the "+
+		"terminal (novox/hq ADR 0272). Nothing was assigned", controllerModule, verb)
+}

cmd/mesh-controller/acts_test.go

@@ -1,3 +1,5 @@
+//go:build integration
+
 package main
 
 import (

cmd/mesh-controller/addresses_integration_test.go

@@ -0,0 +1,228 @@
+//go:build integration
+
+package main
+
+import (
+	"encoding/json"
+	"os"
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/licences"
+)
+
+func TestTheRegistryTrustAndEveryImageFollowThePortTheNodeGaveTheStore(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	register(t, open, aStore())
+	if _, err := assign(ctx, open, "anchor", "distribution"); err != nil {
+		t.Fatal(err)
+	}
+	if err := open.inventory.SetSettings(ctx, "anchor", "distribution",
+		map[string]any{catalogue.PortsSetting: map[string]any{"5000": 5101}}); err != nil {
+		t.Fatal(err)
+	}
+	// A module the mesh built, recorded by digest and path, running on the other machine.
+	if err := open.inventory.RecordBuild(ctx, inventory.Build{
+		ID: "b1", Repository: "r", Module: "app", Commit: "abc",
+		Made: []inventory.Artifact{{Name: "server", Kind: "image",
+			Reference: catalogue.ArtifactStoreScheme + "app/server@" + aDigest}},
+	}); err != nil {
+		t.Fatal(err)
+	}
+	register(t, open, catalogue.Manifest{Module: "app", Version: "1",
+		Resources: []map[string]any{{"id": "server", "type": "container", "name": "mesh-app",
+			"image": catalogue.ArtifactStoreScheme + "app/server@" + aDigest}}})
+	if _, err := assign(ctx, open, "laptop", "app"); err != nil {
+		t.Fatal(err)
+	}
+	// The runtime's trust is the runtime's module's to write (novox/hq ADR 0222): a stand-in for it
+	// asks where this machine reaches the store, as the docker module does.
+	register(t, open, catalogue.Manifest{Module: "runtime", Version: "1",
+		Resources: []map[string]any{{"id": "daemon", "type": "file", "path": "/etc/docker/daemon.json",
+			"into": "json", "content": `{"insecure-registries": ["${seat:mesh-artifact-store:reach}"]}` + "\n"}}})
+	if _, err := assign(ctx, open, "laptop", "runtime"); err != nil {
+		t.Fatal(err)
+	}
+
+	on := map[string]bool{"anchor": true, "laptop": true}
+	node, port, found, err := artifactStoreOnNetwork(ctx, open.inventory, on)
+	if err != nil || !found || node != "anchor" || port != "5101" {
+		t.Fatalf("the store is found on %q:%q (%v, %v); the node put it on 5101", node, port, found, err)
+	}
+
+	var trust string
+	for _, r := range composed(t, open, "laptop").Resources {
+		if r["path"] == "/etc/docker/daemon.json" {
+			trust, _ = r["content"].(string)
+		}
+		if r["id"] == "app.server" && r["image"] != "anchor.internal:5101/app/server@"+aDigest {
+			t.Errorf("the image the mesh built is fetched as %v", r["image"])
+		}
+	}
+	if !strings.Contains(trust, "anchor.internal:5101") || strings.Contains(trust, ":5000") {
+		t.Fatalf("the runtime is told to trust %q; the node put the store on 5101", trust)
+	}
+
+	// And a replay to the catalogue says where the store is now.
+	announced, err := following{open: open}.Announceable(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(announced) != 1 || announced[0].Made[0].Reference != "anchor.internal:5101/app/server@"+aDigest {
+		t.Fatalf("the replay announces %+v", announced)
+	}
+}
+
+func TestTheControlPlaneIsToldWhereTheNodePutTheStoreAndTheBroker(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	raw, err := os.ReadFile("../../module.json")
+	if err != nil {
+		t.Fatal(err)
+	}
+	m, err := catalogue.ParseManifest(raw)
+	if err != nil {
+		t.Fatal(err)
+	}
+	control, err := withSeatPorts(m).Resolve([]catalogue.Built{{Name: "controller", Kind: catalogue.ArtifactBundle,
+		Reference: "https://registry.example/mesh-controller/controller.tar.gz", Digest: aDigest}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	register(t, open, control)
+	register(t, open, catalogue.Manifest{Module: "postgres", Version: "1",
+		Claims:  []catalogue.Claim{{Name: "mesh-store", Scope: catalogue.ScopeMesh}},
+		Listens: []catalogue.Listening{{Port: 5432, From: catalogue.FromMesh}},
+		Resources: []map[string]any{{"id": "server", "type": "container", "name": "mesh-store",
+			"ports": []any{"5432:5432"}, "image": "pg@" + aDigest}}})
+	register(t, open, catalogue.Manifest{Module: "lavinmq", Version: "1",
+		Claims: []catalogue.Claim{{Name: "mesh-broker", Scope: catalogue.ScopeMesh}},
+		Listens: []catalogue.Listening{{Port: 5671, From: catalogue.FromMesh},
+			{Port: 5672, From: catalogue.FromMesh}},
+		Guards: []int{15672},
+		Resources: []map[string]any{{"id": "server", "type": "container", "name": "mesh-broker",
+			"ports": []any{"5671:5671", "5672:5672", "127.0.0.1:15672:15672"}, "image": "mq@" + aDigest}}})
+	// The control plane's own bus user is the installer's, seeded at genesis before the controller
+	// runs (SeedBusUser); without it a push now refuses the credential nobody issued (issue 203).
+	if err := open.inventory.SeedBusUser(ctx, inventory.BusUser{Username: "anchor.mesh-controller",
+		Kind: inventory.BusController, Node: "anchor", Module: "mesh-controller"}, "bootstrap"); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := assign(ctx, open, "anchor", "mesh-controller"); err != nil {
+		t.Fatal(err)
+	}
+	// The store's module is registered and given its port, and NOT assigned: the state genesis
+	// leaves a given-port node in before the foundation is adopted as modules (04-ISSUES/085).
+	if err := open.inventory.SetSettings(ctx, "anchor", "postgres",
+		map[string]any{catalogue.PortsSetting: map[string]any{"5432": 6852}}); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := assign(ctx, open, "anchor", "lavinmq"); err != nil {
+		t.Fatal(err)
+	}
+	if err := open.inventory.SetSettings(ctx, "anchor", "lavinmq",
+		map[string]any{catalogue.PortsSetting: map[string]any{"5672": 5679}}); err != nil {
+		t.Fatal(err)
+	}
+
+	var env map[string]any
+	for _, r := range composed(t, open, "anchor").Resources {
+		if r["id"] == "mesh-controller.controller" {
+			env, _ = r["env"].(map[string]any)
+		}
+	}
+	if env == nil {
+		t.Fatal("the control plane's process is not in its own node's declaration")
+	}
+	for key, want := range map[string]string{
+		"MESH_STORE_INVENTORY_PORT": "6852",
+		"MESH_STORE_IDENTITY_PORT":  "6852",
+		"MESH_STORE_LICENCES_PORT":  "6852",
+		"MESH_BROKER_AMQP_PORT":     "5679",
+		// Neither given nor assigned by the mesh: the manifest's own number is NOT the answer,
+		// because the sealed value beside it carries the port genesis wrote (finding F3).
+		"MESH_BROKER_ADDRESS_PORT":    "",
+		"MESH_BROKER_MANAGEMENT_PORT": "",
+	} {
+		if env[key] != want {
+			t.Errorf("the control plane is told %s=%v; the node says %q", key, env[key], want)
+		}
+	}
+}
+
+func aLoneNode(t *testing.T) *stores {
+	t.Helper()
+	inventory.ForTest(t)
+	licences.ForTest(t)
+	open, err := openStores(t.Context())
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(open.Close)
+	for _, m := range provided {
+		if err := open.inventory.Provide(t.Context(), m); err != nil {
+			t.Fatal(err)
+		}
+	}
+	record, err := open.inventory.AddNode(t.Context(), "anchor")
+	if err != nil {
+		t.Fatal(err)
+	}
+	reported, _ := json.Marshal(map[string]any{"capabilities": []map[string]any{
+		{"name": "container-runtime", "present": true}}})
+	var profile map[string]any
+	_ = json.Unmarshal(reported, &profile)
+	if err := open.inventory.RecordProfile(t.Context(), record.ID, profile); err != nil {
+		t.Fatal(err)
+	}
+	if err := open.inventory.RecordSealingKey(t.Context(), record.ID, aPublicKey(t)); err != nil {
+		t.Fatal(err)
+	}
+	return open
+}
+
+func TestOnANodeWithNoNetworkTheStoreIsReachedByLoopback(t *testing.T) {
+	open := aLoneNode(t)
+	ctx := t.Context()
+	register(t, open, aStore())
+	register(t, open, catalogue.Manifest{Module: "builder", Version: "1",
+		Requires: []string{catalogue.ArtifactStoreProvision},
+		Resources: []map[string]any{{"id": "server", "type": "container", "name": "mesh-builder",
+			"image": "registry.example/mesh-builder@" + aDigest}}})
+	if err := open.inventory.RecordBuild(ctx, inventory.Build{
+		ID: "b1", Repository: "r", Module: "postgres", Commit: "abc",
+		Made: []inventory.Artifact{{Name: "runtime", Kind: "image",
+			Reference: catalogue.ArtifactStoreScheme + "postgres/runtime@" + aDigest}},
+	}); err != nil {
+		t.Fatal(err)
+	}
+	register(t, open, catalogue.Manifest{Module: "postgres", Version: "1",
+		Resources: []map[string]any{{"id": "runtime", "type": "container", "name": "mesh-postgres",
+			"image": catalogue.ArtifactStoreScheme + "postgres/runtime@" + aDigest}}})
+	for _, module := range []string{"distribution", "builder", "postgres"} {
+		if _, err := assign(ctx, open, "anchor", module); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if err := open.inventory.SetSettings(ctx, "anchor", "distribution",
+		map[string]any{catalogue.PortsSetting: map[string]any{"5000": 5100}}); err != nil {
+		t.Fatal(err)
+	}
+
+	var image any
+	for _, r := range composed(t, open, "anchor").Resources {
+		if r["id"] == "postgres.runtime" {
+			image = r["image"]
+		}
+	}
+	if image != "127.0.0.1:5100/postgres/runtime@"+aDigest {
+		t.Fatalf("on the store's own node, off any network, the image is fetched as %v", image)
+	}
+	held := heldBy(ctx)
+	if got := held["postgres/runtime"]; got != "127.0.0.1:5100/postgres/runtime@"+aDigest {
+		t.Fatalf("a builder beside the store is handed the base %q", got)
+	}
+}

cmd/mesh-controller/addresses_test.go

@@ -0,0 +1,139 @@
+package main
+
+import (
+	"encoding/json"
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// An address is read from the node's settings where it is used, never recorded with a port
+// (novox/hq 04-ISSUES/102). Three readers did not follow the setting; each is held to it here.
+
+var aDigest = "sha256:" + strings.Repeat("e", 64)
+
+// **A build is recorded by digest and path**, whatever address the builder pushed to — what it
+// made and what it stood on both; an image the module runs from elsewhere is left where it says.
+func TestABuildIsRecordedWithoutTheStoresAddress(t *testing.T) {
+	manifest, _ := json.Marshal(map[string]any{
+		"module": "gitea", "version": "1",
+		"resources": []map[string]any{
+			{"id": "server", "type": "container", "name": "mesh-gitea",
+				"image": "anchor.internal:5100/gitea/server@" + aDigest},
+			{"id": "config", "type": "archive", "path": "/etc/gitea", "digest": aDigest,
+				"source": "http://anchor.internal:5100/v2/gitea/config/blobs/" + aDigest},
+			{"id": "cache", "type": "container", "name": "mesh-gitea-cache",
+				"image": "valkey/valkey@" + aDigest},
+		},
+	})
+	kept := buildFrom(link.BuildResult{
+		ID: "b1", Repository: "https://forge.example/gitea.git", Commit: "abc", On: "laptop",
+		Manifest: manifest,
+		Made: []link.MadeArtifact{
+			{Name: "server", Kind: "image", Reference: "anchor.internal:5100/gitea/server@" + aDigest},
+			{Name: "config", Kind: "archive", Reference: "http://anchor.internal:5100/v2/gitea/config/blobs/" + aDigest},
+		},
+		Against: []string{"anchor.internal:5100/mesh-tools/runtime@" + aDigest},
+	})
+	if kept.Module != "gitea" {
+		t.Fatalf("the module was not read from the recorded manifest: %q", kept.Module)
+	}
+	if kept.Made[0].Reference != catalogue.ArtifactStoreScheme+"gitea/server@"+aDigest {
+		t.Errorf("the image is recorded as %q, address and all", kept.Made[0].Reference)
+	}
+	if kept.Made[1].Reference != catalogue.ArtifactStoreScheme+"gitea/config/blobs/"+aDigest {
+		t.Errorf("the archive is recorded as %q, address and all", kept.Made[1].Reference)
+	}
+	recorded, err := catalogue.ParseManifest(kept.Manifest)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := recorded.Resources[0]["image"]; got != catalogue.ArtifactStoreScheme+"gitea/server@"+aDigest {
+		t.Errorf("the recorded manifest's image is %v", got)
+	}
+	if got := recorded.Resources[1]["source"]; got != catalogue.ArtifactStoreScheme+"gitea/config/blobs/"+aDigest {
+		t.Errorf("the recorded manifest's archive is %v", got)
+	}
+	if got := recorded.Resources[2]["image"]; got != "valkey/valkey@"+aDigest {
+		t.Errorf("an image the build did not make was rewritten: %v", got)
+	}
+	if strings.Contains(string(kept.Manifest), "anchor.internal:5100") {
+		t.Errorf("the recorded manifest still carries the store's address:\n%s", kept.Manifest)
+	}
+	// What the build stood on is an edge to another module's artifact, and it is recorded the way
+	// that artifact is: by path in the store, so the edge still names the same thing when the
+	// store answers at another address.
+	if kept.Against[0] != catalogue.ArtifactStoreScheme+"mesh-tools/runtime@"+aDigest {
+		t.Errorf("what the build stood on was recorded by address: %v", kept.Against)
+	}
+}
+
+// aStore is a module offering the artifact store on 5000, published the long way as the
+// distribution module does, so a node may be given another number for it.
+func aStore() catalogue.Manifest {
+	return catalogue.Manifest{Module: "distribution", Version: "1",
+		Provides: []catalogue.Offer{{Name: catalogue.ArtifactStoreProvision, Scope: catalogue.ScopeMesh}},
+		Serves:   map[string]map[string]any{catalogue.ArtifactStoreProvision: {"port": float64(5000)}},
+		Listens:  []catalogue.Listening{{Port: 5000, From: catalogue.FromMesh}},
+		Resources: []map[string]any{{"id": "store", "type": "container", "name": "mesh-registry",
+			"ports": []any{"5000:5000"}, "image": "registry@" + aDigest}}}
+}
+
+// **The trust a machine writes for the store, and the address every built image is fetched
+// through, say the port the node gave the store** — not the catalogue's number.
+
+// **The control plane's own connections say the port the node gave the store and the broker.**
+//
+// Composed from the control plane's own manifest against a real inventory: the store's module is
+// given 6852 on this node the way genesis or an operator gives it, and the control plane's
+// process is told so beside the sealed connection genesis wrote.
+
+// withSeatPorts is the control plane's manifest with the seat placeholders in its environment —
+// added here until module.json carries them (the manifest lands one commit after the code that
+// fills it, so a control plane one build behind never sees a placeholder it cannot fill).
+func withSeatPorts(m catalogue.Manifest) catalogue.Manifest {
+	seatPorts := map[string]string{
+		"MESH_STORE_INVENTORY_PORT":   "${seat:mesh-store:5432}",
+		"MESH_STORE_IDENTITY_PORT":    "${seat:mesh-store:5432}",
+		"MESH_STORE_LICENCES_PORT":    "${seat:mesh-store:5432}",
+		"MESH_BROKER_AMQP_PORT":       "${seat:mesh-broker:5672}",
+		"MESH_BROKER_MANAGEMENT_PORT": "${seat:mesh-broker:15672}",
+		"MESH_BROKER_ADDRESS_PORT":    "${seat:mesh-broker:5671}",
+	}
+	out := m
+	out.Resources = nil
+	for _, r := range m.Resources {
+		if r["type"] != "container" && r["type"] != "process" {
+			out.Resources = append(out.Resources, r)
+			continue
+		}
+		copied := map[string]any{}
+		for k, v := range r {
+			copied[k] = v
+		}
+		env := map[string]any{}
+		if had, ok := r["env"].(map[string]any); ok {
+			for k, v := range had {
+				env[k] = v
+			}
+		}
+		for k, v := range seatPorts {
+			if _, said := env[k]; !said {
+				env[k] = v
+			}
+		}
+		copied["env"] = env
+		out.Resources = append(out.Resources, copied)
+	}
+	return out
+}
+
+// aLoneNode is one capable machine with nothing placed on any network — the control-node during
+// genesis, before the "network" step, which is after the store, the broker, the vault and the
+// catalogue have each been built and pushed (finding F2).
+
+// **Before the network exists, the store's own node reaches it by loopback** — never refused,
+// never handed the scheme: a genesis pushes the store, the broker, the vault and the catalogue to
+// a node on no network, and builds the catalogue on a base it must be able to pull.

cmd/mesh-controller/adopting_test.go

@@ -0,0 +1,643 @@
+//go:build integration
+
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"net/http"
+	"reflect"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+	"github.com/novox/mesh-controller/internal/overlay"
+)
+
+// novox/hq ADR 0100: taking a module is its cutover; converging a node is one act, previewed, and
+// refused while a found container is held; returning to adopted keeps what was taken.
+
+// anAdoptedAnchor is aMesh with the anchor adopted, running a served module the predecessor also
+// runs and a module with only a file, and a filter module in the catalogue.
+func anAdoptedAnchor(t *testing.T) (*stores, *[]string) {
+	t.Helper()
+	open := aMesh(t)
+	ctx := t.Context()
+	register(t, open, catalogue.Manifest{Module: "hello-web", Version: "1",
+		Listens: []catalogue.Listening{{Port: 8080, From: catalogue.FromEverywhere}},
+		Resources: []map[string]any{
+			{"id": "page", "type": "file", "path": "/var/lib/hello-web/index.html", "content": "hi"},
+			{"id": "server", "type": "container", "name": "hello-web", "ports": []any{"8080:80"},
+				"image": "registry.example/hello@sha256:" + strings.Repeat("a", 64)},
+		}})
+	register(t, open, catalogue.Manifest{Module: "notes", Version: "1",
+		Resources: []map[string]any{
+			{"id": "conf", "type": "file", "path": "/etc/notes.conf", "content": "x"},
+		}})
+	register(t, open, catalogue.Manifest{Module: "nftables", Version: "1",
+		Filtering: &catalogue.Filtering{Into: "/etc/nftables.conf"},
+		Resources: []map[string]any{{"id": "load", "type": "service", "unit": "mesh-filter.service",
+			"state": "running", "restart-on": []any{"filtering"}}}})
+	if err := open.inventory.SetAdopted(ctx, "anchor", true); err != nil {
+		t.Fatal(err)
+	}
+	for _, m := range []string{"hello-web", "notes"} {
+		if _, err := assign(ctx, open, "anchor", m); err != nil {
+			t.Fatal(err)
+		}
+	}
+	sent := &[]string{}
+	saved := sendNodes
+	sendNodes = func(_ context.Context, _ *stores, names []string) error {
+		*sent = append(*sent, names...)
+		return nil
+	}
+	t.Cleanup(func() { sendNodes = saved })
+	return open, sent
+}
+
+// reportsHolding has the anchor report, on what it was last sent, holding what is given.
+func reportsHolding(t *testing.T, open *stores, held ...link.Held) {
+	t.Helper()
+	reportsReaching(t, open, []link.Reach{
+		{Protocol: "tcp", Address: "0.0.0.0", Port: 22, By: "sshd"},
+		{Protocol: "tcp", Address: "0.0.0.0", Port: 8080, By: "hello-web", Published: true,
+			ContainerPort: 80},
+		{Protocol: "tcp", Address: "0.0.0.0", Port: 5000, By: "predecessor-registry",
+			Published: true, ContainerPort: 5000},
+		{Protocol: "tcp", Address: "127.0.0.1", Port: 15672, By: "mesh-broker",
+			Published: true, ContainerPort: 15672},
+	}, held...)
+}
+
+// reportsReaching has the anchor report, on what it was last sent, what is reachable on it and
+// holding what is given.
+func reportsReaching(t *testing.T, open *stores, reachable []link.Reach, held ...link.Held) {
+	t.Helper()
+	ctx := t.Context()
+	body, err := composed(t, open, "anchor").Body()
+	if err != nil {
+		t.Fatal(err)
+	}
+	record, err := open.inventory.NodeByName(ctx, "anchor")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := open.inventory.RecordSent(ctx, record.ID, digestOf(body), nil); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := (link.Enrolment{Inventory: open.inventory}).Heard(ctx, link.Report{
+		Node: "anchor", Applied: []string{"hello-web.x"}, Declared: digestOf(body),
+		Firewall: "ufw", Held: held, Reachable: reachable,
+		// A machine says which of its links face outside on every apply (novox/hq ADR 0140), and a
+		// filter is not sent to one that has not. The anchor reports one, as a real host does; this
+		// fixture lacked it from 2026-09-28 and nothing ran the test (issue 177).
+		Outward: []string{"eth0"},
+		// And what filters it (ADR 0168): its front end, the runtime's own, and a chain a
+		// predecessor left in the runtime's user chain.
+		Filters: anchorFilters,
+	}); err != nil {
+		t.Fatal(err)
+	}
+}
+
+// anchorFilters is what the adopted anchor says filters it: ufw's chains, the runtime's, and a
+// predecessor's chain the mesh did not write.
+var anchorFilters = []link.Filter{
+	{Where: "table ip filter, chain ufw-reject-input", Owner: "found-firewall", Refuses: "reject"},
+	{Where: "table ip filter, chain DOCKER", Owner: "runtime", Refuses: `iifname != "docker0" oifname "docker0" drop`},
+	{Where: "table ip filter, chain DOCKER-USER", Owner: "other", Refuses: `iifname "eth0" tcp dport 6000 drop`},
+}
+
+var (
+	heldContainer = link.Held{ID: "hello-web.server", Module: "hello-web", Kind: "container",
+		Target: "hello-web", Since: time.Now()}
+	heldFile = link.Held{ID: "notes.conf", Module: "notes", Kind: "file",
+		Target: "/etc/notes.conf", Since: time.Now(), Kept: "/var/lib/mesh-host/kept/abc-notes.conf"}
+)
+
+func TestTakingAModuleNotOnTheNodeIsRefused(t *testing.T) {
+	open, _ := anAdoptedAnchor(t)
+	if _, err := take(t.Context(), open, "anchor", "nftables", takeOptions{Yes: true}); !errors.Is(err, inventory.ErrNotAssigned) {
+		t.Fatalf("taking an unassigned module gave %v", err)
+	}
+	if _, err := take(t.Context(), open, "laptop", "network", takeOptions{Yes: true}); !errors.Is(err, inventory.ErrNotAdopted) {
+		t.Fatalf("taking on a converged node gave %v", err)
+	}
+}
+
+func TestConvergingIsRefusedOnAPreviewThatWouldBeStale(t *testing.T) {
+	open, sent := anAdoptedAnchor(t)
+	_, err := converge(t.Context(), open, "anchor", false, "", "")
+	if err == nil || !strings.Contains(err.Error(), "has not reported") {
+		t.Fatalf("a node that never reported was previewed: %v", err)
+	}
+	if len(*sent) != 0 {
+		t.Fatal("a refused converge sent something")
+	}
+}
+
+func TestTheFlipIsRefusedWhileAFoundContainerIsHeld(t *testing.T) {
+	open, sent := anAdoptedAnchor(t)
+	reportsHolding(t, open, heldContainer, heldFile)
+	_, err := converge(t.Context(), open, "anchor", true, "", "")
+	if err == nil || !strings.Contains(err.Error(), "take anchor hello-web once its data has moved") {
+		t.Fatalf("the flip was not refused while hello-web holds its found container: %v", err)
+	}
+	if n, _ := open.inventory.NodeByName(t.Context(), "anchor"); !n.Adopted || len(*sent) != 0 {
+		t.Fatal("a refused flip changed something")
+	}
+}
+
+func TestTakingNamesWhatItReplaces(t *testing.T) {
+	open, _ := anAdoptedAnchor(t)
+	reportsHolding(t, open, heldContainer, heldFile)
+	ctx := t.Context()
+	// The machine holds something for the module, so the take acts on the preview the operator
+	// saw and names its digest (novox/hq ADR 0163).
+	preview, err := take(ctx, open, "anchor", "hello-web", takeOptions{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	saw := takeDigestIn(t, preview)
+	if !strings.Contains(preview, "nothing taken; `take anchor hello-web --yes "+saw+"`") {
+		t.Fatalf("the preview does not say how to act on it:\n%s", preview)
+	}
+	if taken, _ := open.inventory.Taken(ctx, "anchor"); len(taken) != 0 {
+		t.Fatal("the preview took something")
+	}
+	if _, err := take(ctx, open, "anchor", "hello-web", takeOptions{Yes: true}); err == nil || !strings.Contains(err.Error(), "name its digest") {
+		t.Fatalf("--yes without the digest was not refused: %v", err)
+	}
+	said, err := take(ctx, open, "anchor", "hello-web", takeOptions{Yes: true, Digest: saw})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(said, "container hello-web (hello-web.server)") ||
+		!strings.Contains(said, "push anchor") {
+		t.Fatalf("taking did not say what it replaces and what to run:\n%s", said)
+	}
+}
+
+// takeDigestIn is the digest a take's preview printed.
+func takeDigestIn(t *testing.T, preview string) string {
+	t.Helper()
+	for _, line := range strings.Split(preview, "\n") {
+		if fields := strings.Fields(line); len(fields) == 2 && fields[0] == "preview" {
+			return fields[1]
+		}
+	}
+	t.Fatalf("the preview printed no digest:\n%s", preview)
+	return ""
+}
+
+// A take acts on the preview the operator saw, and on an account of the machine that is still the
+// machine: a changed preview and a stale account refuse (novox/hq ADR 0163, rule 1).
+func TestATakeIsRefusedOnAChangedPreviewOrAStaleAccount(t *testing.T) {
+	open, _ := anAdoptedAnchor(t)
+	ctx := t.Context()
+	reportsHolding(t, open, heldContainer, heldFile)
+	preview, err := take(ctx, open, "anchor", "hello-web", takeOptions{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	saw := takeDigestIn(t, preview)
+
+	// The machine reports again, and what it holds has changed: the found container now carries
+	// facts the preview never showed.
+	changed := heldContainer
+	changed.Facts = map[string]any{"image": "hello:2", "declared_image": "registry.example/hello"}
+	reportsHolding(t, open, changed, heldFile)
+	_, err = take(ctx, open, "anchor", "hello-web", takeOptions{Yes: true, Digest: saw})
+	if err == nil || !strings.Contains(err.Error(), "has changed since preview "+saw) {
+		t.Fatalf("a changed preview was acted on: %v", err)
+	}
+	if taken, _ := open.inventory.Taken(ctx, "anchor"); len(taken) != 0 {
+		t.Fatal("a refused take took something")
+	}
+
+	// And an account older than the flip allows.
+	preview, err = take(ctx, open, "anchor", "hello-web", takeOptions{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	saw = takeDigestIn(t, preview)
+	saved := reportFreshFor
+	reportFreshFor = -time.Second
+	defer func() { reportFreshFor = saved }()
+	_, err = take(ctx, open, "anchor", "hello-web", takeOptions{Yes: true, Digest: saw})
+	if err == nil || !strings.Contains(err.Error(), "a take acts only on an account newer than") {
+		t.Fatalf("a stale account was acted on: %v", err)
+	}
+	reportFreshFor = saved
+	if _, err := take(ctx, open, "anchor", "hello-web", takeOptions{Yes: true, Digest: saw}); err != nil {
+		t.Fatal(err)
+	}
+	// A module the machine holds nothing for has nothing to compare: --yes alone suffices.
+	if _, err := take(ctx, open, "anchor", "notes", takeOptions{Yes: true}); err == nil {
+		// notes holds a file, so this one needs the digest too.
+		t.Fatal("notes holds a found file and was taken without a digest")
+	}
+}
+
+func TestConvergingPreviewsThenChangesAndAdoptingKeepsWhatWasTaken(t *testing.T) {
+	open, sent := anAdoptedAnchor(t)
+	ctx := t.Context()
+	if _, err := take(ctx, open, "anchor", "hello-web", takeOptions{Yes: true}); err != nil {
+		t.Fatal(err)
+	}
+	reportsHolding(t, open, heldFile)
+
+	preview, err := converge(ctx, open, "anchor", false, "", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, want := range []string{
+		"tcp/8080 hello-web (published, container port 80)",
+		"declared by hello-web (from anywhere)",
+		"WILL CLOSE — no module assigned here declares it",
+		// The anchor faces inward and is on the private network: the derived filter admits ssh
+		// from the mesh only.
+		"WILL CLOSE to everything outside the private network — ssh stays open from the mesh",
+		"notes\n      replacing the found file /etc/notes.conf (notes.conf), original kept at",
+		"assigns nftables",
+		"the found firewall (ufw) is disabled, never flushed",
+		// What it routes is not a listener: said not to be previewed, and to be dropped.
+		"not previewed: traffic the machine routes that is not a published port",
+		"the derived filter drops it unless a module declares it",
+	} {
+		if !strings.Contains(preview, want) {
+			t.Errorf("the preview does not say %q:\n%s", want, preview)
+		}
+	}
+	if strings.Contains(preview, "15672") {
+		t.Errorf("a loopback listener is in the preview:\n%s", preview)
+	}
+	// What filters the machine now, and the fate of each (novox/hq ADR 0168): the predecessor's
+	// chain is named as not the mesh's and left, so the reader knows before the flip.
+	for _, want := range []string{
+		"table ip filter, chain DOCKER-USER",
+		"NOT THE MESH'S; left in force",
+		`iifname "eth0" tcp dport 6000 drop`,
+		"table ip filter, chain ufw-reject-input",
+		"the found firewall's; retired with it",
+		"the container runtime's own; left",
+	} {
+		if !strings.Contains(preview, want) {
+			t.Errorf("the preview does not say %q:\n%s", want, preview)
+		}
+	}
+	for _, line := range strings.Split(preview, "\n") {
+		if strings.Contains(line, "5000") && !strings.Contains(line, "WILL CLOSE") {
+			t.Errorf("an undeclared published port is not said to close: %s", line)
+		}
+	}
+	if n, _ := open.inventory.NodeByName(ctx, "anchor"); !n.Adopted || len(*sent) != 0 {
+		t.Fatal("the preview changed something")
+	}
+
+	if _, err := converge(ctx, open, "anchor", true, digestIn(t, preview), ""); err != nil {
+		t.Fatal(err)
+	}
+	n, _ := open.inventory.NodeByName(ctx, "anchor")
+	if n.Adopted {
+		t.Fatal("converge --yes left the node adopted")
+	}
+	taken, _ := open.inventory.Taken(ctx, "anchor")
+	if !reflect.DeepEqual(taken, []string{"hello-web", overlay.Name, "nftables", "notes"}) {
+		t.Fatalf("the flip took %v", taken)
+	}
+	if !reflect.DeepEqual(*sent, []string{"anchor"}) {
+		t.Fatalf("the flip sent %v", *sent)
+	}
+	declared := composed(t, open, "anchor")
+	if declared.Adoption != nil {
+		t.Fatal("a converged node is still sent an adoption envelope")
+	}
+	if !hasID(declared.Resources, "nftables.filtering") {
+		t.Fatal("the converged node is not declared the mesh's filter")
+	}
+
+	if _, err := adopt(ctx, open, "anchor"); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := adopt(ctx, open, "anchor"); err == nil {
+		t.Fatal("adopting an adopted node was not refused")
+	}
+	again, _ := open.inventory.Taken(ctx, "anchor")
+	if !reflect.DeepEqual(again, taken) {
+		t.Fatalf("returning to adopted lost what was taken: %v", again)
+	}
+	declared = composed(t, open, "anchor")
+	if declared.Adoption == nil || len(declared.Adoption.Untaken) != 0 {
+		t.Fatalf("returned to adopted, the envelope is %+v", declared.Adoption)
+	}
+	if hasID(declared.Resources, "nftables.filtering") || hasID(declared.Resources, "nftables.load") {
+		t.Fatal("returned to adopted, the mesh's filter is still declared")
+	}
+}
+
+func hasID(resources []map[string]any, id string) bool {
+	for _, r := range resources {
+		if r["id"] == id {
+			return true
+		}
+	}
+	return false
+}
+
+// The command API refuses a flip exactly as the command line does, in the same words.
+func TestTheApiRefusesTheFlipInTheCommandLinesWords(t *testing.T) {
+	open, _ := anAdoptedAnchor(t)
+	reportsHolding(t, open, heldContainer)
+	_, direct := converge(t.Context(), open, "anchor", true, "", "")
+	if direct == nil {
+		t.Fatal("the flip was not refused")
+	}
+	got := asking(t, letIn{}, "POST", "/converge", `{"node":"anchor","yes":true}`)
+	if got.Code != http.StatusConflict {
+		t.Fatalf("got %d: %s", got.Code, got.Body.String())
+	}
+	var said map[string]any
+	if err := json.Unmarshal(got.Body.Bytes(), &said); err != nil {
+		t.Fatal(err)
+	}
+	if said["refused"] != direct.Error() {
+		t.Fatalf("the API said %q and the command line %q", said["refused"], direct.Error())
+	}
+	if got := asking(t, letIn{}, "POST", "/take", `{"node":"anchor"}`); got.Code != http.StatusBadRequest {
+		t.Fatalf("a take naming no module got %d", got.Code)
+	}
+}
+
+// novox/hq ADR 0100: the preview says what the derived filter does, rendered as it is rendered. On
+// a machine that faces inward, ssh is admitted from the private network only, and a port a module
+// admits from the mesh only closes to everything outside it: both are said to close.
+func TestThePreviewSaysWhatNarrowsToTheMeshCloses(t *testing.T) {
+	open, _ := anAdoptedAnchor(t)
+	ctx := t.Context()
+	register(t, open, catalogue.Manifest{Module: "store", Version: "1",
+		Listens: []catalogue.Listening{{Port: 5432, From: catalogue.FromMesh}}})
+	if _, err := assign(ctx, open, "anchor", "store"); err != nil {
+		t.Fatal(err)
+	}
+	reportsReaching(t, open, []link.Reach{
+		{Protocol: "tcp", Address: "0.0.0.0", Port: 22, By: "sshd"},
+		{Protocol: "tcp", Address: "0.0.0.0", Port: 5432, By: "postgres"},
+		{Protocol: "tcp", Address: "10.77.0.1", Port: 5432, By: "postgres"},
+		{Protocol: "tcp", Address: "0.0.0.0", Port: 8080, By: "hello-web", Published: true,
+			ContainerPort: 80},
+	})
+	preview, err := converge(ctx, open, "anchor", false, "", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	lines := map[string]string{}
+	for _, line := range strings.Split(preview, "\n") {
+		fields := strings.Fields(line)
+		if len(fields) > 1 && strings.HasPrefix(fields[0], "tcp/") {
+			lines[fields[0]+" "+fields[1]] += line + "\n"
+		}
+	}
+	if got := lines["tcp/22 sshd"]; !strings.Contains(got, "WILL CLOSE to everything outside "+
+		"the private network") {
+		t.Errorf("ssh on an inward machine is not said to close outside the mesh:\n%s", preview)
+	}
+	store := lines["tcp/5432 postgres"]
+	if strings.Count(store, "WILL CLOSE to everything outside the private network") != 1 ||
+		!strings.Contains(store, "declared by store (from mesh)") {
+		t.Errorf("the store's narrowing is not said to close, or its mesh address is:\n%s", preview)
+	}
+	if got := lines["tcp/8080 hello-web"]; !strings.Contains(got, "declared by hello-web (from anywhere)") {
+		t.Errorf("a port open to everywhere is not said to stay:\n%s", preview)
+	}
+}
+
+// digestIn is the digest a converge preview printed.
+func digestIn(t *testing.T, preview string) string {
+	t.Helper()
+	for _, line := range strings.Split(preview, "\n") {
+		if fields := strings.Fields(line); len(fields) == 2 && fields[0] == "preview" {
+			return fields[1]
+		}
+	}
+	t.Fatalf("the preview printed no digest:\n%s", preview)
+	return ""
+}
+
+// The flip acts on the preview the operator saw: it names that preview's digest, and it is refused
+// when the digest is missing, when anything the preview says has changed since, or when the node's
+// account of itself is too old to be the machine as it is.
+func TestTheFlipActsOnlyOnThePreviewTheOperatorSaw(t *testing.T) {
+	open, sent := anAdoptedAnchor(t)
+	ctx := t.Context()
+	if _, err := take(ctx, open, "anchor", "hello-web", takeOptions{Yes: true}); err != nil {
+		t.Fatal(err)
+	}
+	reportsHolding(t, open, heldFile)
+	preview, err := converge(ctx, open, "anchor", false, "", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	saw := digestIn(t, preview)
+	if !strings.Contains(preview, "converge anchor --yes "+saw) {
+		t.Fatalf("the preview does not say how to act on it:\n%s", preview)
+	}
+	unchanged := func() {
+		t.Helper()
+		if n, _ := open.inventory.NodeByName(ctx, "anchor"); !n.Adopted || len(*sent) != 0 {
+			t.Fatal("a refused flip changed something")
+		}
+	}
+
+	if _, err := converge(ctx, open, "anchor", true, "", ""); err == nil ||
+		!strings.Contains(err.Error(), "--yes "+saw) {
+		t.Fatalf("a flip naming no preview was not refused: %v", err)
+	}
+	unchanged()
+
+	// Something new is reachable: the preview the operator saw is not what would happen.
+	reportsReaching(t, open, []link.Reach{
+		{Protocol: "tcp", Address: "0.0.0.0", Port: 22, By: "sshd"},
+		{Protocol: "tcp", Address: "0.0.0.0", Port: 8080, By: "hello-web", Published: true,
+			ContainerPort: 80},
+		{Protocol: "tcp", Address: "0.0.0.0", Port: 6000, By: "something-new"},
+	}, heldFile)
+	_, err = converge(ctx, open, "anchor", true, saw, "")
+	if err == nil || !strings.Contains(err.Error(), "has changed since preview "+saw) {
+		t.Fatalf("a flip on a changed preview was not refused: %v", err)
+	}
+	unchanged()
+
+	// An account older than the flip trusts is refused, whatever digest is named.
+	again, err := converge(ctx, open, "anchor", false, "", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	saved := reportFreshFor
+	reportFreshFor = time.Nanosecond
+	_, err = converge(ctx, open, "anchor", true, digestIn(t, again), "")
+	reportFreshFor = saved
+	if err == nil || !strings.Contains(err.Error(), "wait for its next report") {
+		t.Fatalf("a flip on an old account was not refused: %v", err)
+	}
+	unchanged()
+
+	if _, err := converge(ctx, open, "anchor", true, digestIn(t, again), ""); err != nil {
+		t.Fatalf("the flip on the preview just seen was refused: %v", err)
+	}
+	if n, _ := open.inventory.NodeByName(ctx, "anchor"); n.Adopted {
+		t.Fatal("the flip did not converge the node")
+	}
+}
+
+// The flip holds the node from its checks to its send, so a push composed meanwhile waits and is
+// composed after it — never sent after it with the node still adopted. And the send inside the
+// flip is not made to wait on the flip's own hold.
+func TestTheFlipHoldsTheNodeWhileItSends(t *testing.T) {
+	open, _ := anAdoptedAnchor(t)
+	ctx := t.Context()
+	if _, err := take(ctx, open, "anchor", "hello-web", takeOptions{Yes: true}); err != nil {
+		t.Fatal(err)
+	}
+	reportsHolding(t, open, heldFile)
+	preview, err := converge(ctx, open, "anchor", false, "", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	var heldElsewhere, heldHere error
+	sendNodes = func(inner context.Context, open *stores, names []string) error {
+		// Another caller cannot hold the node while the flip sends it.
+		waiting, cancel := context.WithTimeout(ctx, 300*time.Millisecond)
+		defer cancel()
+		if release, err := open.inventory.HoldNodes(waiting, names); err == nil {
+			release()
+			heldElsewhere = errors.New("another caller held the node while the flip sent it")
+		}
+		// The flip's own send holds it without waiting on itself.
+		_, release, err := holdNodes(inner, open, names)
+		if err != nil {
+			heldHere = err
+			return err
+		}
+		release()
+		return nil
+	}
+	if _, err := converge(ctx, open, "anchor", true, digestIn(t, preview), ""); err != nil {
+		t.Fatal(err)
+	}
+	if heldElsewhere != nil || heldHere != nil {
+		t.Fatalf("%v %v", heldElsewhere, heldHere)
+	}
+	// And given back once it is done.
+	release, err := open.inventory.HoldNodes(ctx, []string{"anchor"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	release()
+}
+
+// novox/hq ADR 0103: the preview names every kind of thing a module the flip takes holds as found,
+// not only its files, and the digest changes when any of them does.
+func TestThePreviewNamesEveryHeldKind(t *testing.T) {
+	open, _ := anAdoptedAnchor(t)
+	ctx := t.Context()
+	if _, err := take(ctx, open, "anchor", "hello-web", takeOptions{Yes: true}); err != nil {
+		t.Fatal(err)
+	}
+	since := time.Now()
+	held := []link.Held{heldFile,
+		{ID: "notes.data", Module: "notes", Kind: "directory", Target: "/var/lib/notes", Since: since},
+		{ID: "notes.daemon", Module: "notes", Kind: "service", Target: "notes.service", Since: since},
+		{ID: "notes.seed", Module: "notes", Kind: "archive", Target: "/srv/notes", Since: since},
+		{ID: "notes.worker", Module: "notes", Kind: "process", Target: "notes-worker", Since: since},
+		{ID: "notes.account", Module: "notes", Kind: "user", Target: "notes", Since: since},
+	}
+	reportsHolding(t, open, held...)
+	preview, err := converge(ctx, open, "anchor", false, "", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, want := range []string{
+		"replacing the found directory /var/lib/notes (notes.data)",
+		"replacing the found service notes.service (notes.daemon)",
+		"replacing the found archive /srv/notes (notes.seed)",
+		"replacing the found process notes-worker (notes.worker)",
+		"replacing the found user notes (notes.account)",
+	} {
+		if !strings.Contains(preview, want) {
+			t.Errorf("the preview does not say %q:\n%s", want, preview)
+		}
+	}
+	reportsHolding(t, open, held[:len(held)-1]...)
+	fewer, err := converge(ctx, open, "anchor", false, "", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if digestIn(t, fewer) == digestIn(t, preview) {
+		t.Fatal("the digest does not change with what is held")
+	}
+}
+
+// novox/hq ADR 0100: the flip acts on what the node said is reachable, so an account naming nothing
+// is refused. Every machine that is up answers on ssh; nothing reported means the host's collectors
+// did not, and flipping would close ports the preview never named.
+func TestTheFlipIsRefusedOnAnAccountNamingNothingReachable(t *testing.T) {
+	open, sent := anAdoptedAnchor(t)
+	ctx := t.Context()
+	if _, err := take(ctx, open, "anchor", "hello-web", takeOptions{Yes: true}); err != nil {
+		t.Fatal(err)
+	}
+	// Only a loopback listener: nothing off the machine, which is the same silence.
+	reportsReaching(t, open, []link.Reach{
+		{Protocol: "tcp", Address: "127.0.0.1", Port: 15672, By: "mesh-broker"},
+	}, heldFile)
+	preview, err := converge(ctx, open, "anchor", false, "", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !strings.Contains(preview, "this account looks partial") {
+		t.Errorf("the preview does not mark a partial account:\n%s", preview)
+	}
+	_, err = converge(ctx, open, "anchor", true, digestIn(t, preview), "")
+	if err == nil || !strings.Contains(err.Error(), "says nothing is reachable on it") {
+		t.Fatalf("the flip was not refused on an account naming nothing: %v", err)
+	}
+	if n, _ := open.inventory.NodeByName(ctx, "anchor"); !n.Adopted || len(*sent) != 0 {
+		t.Fatal("a refused flip changed something")
+	}
+}
+
+// An assignment cannot land between a preview and the flip that takes every module: assigning
+// holds the node, so it waits for whatever is converging it.
+func TestAssigningWaitsForWhateverIsConvergingTheNode(t *testing.T) {
+	open, _ := anAdoptedAnchor(t)
+	ctx := t.Context()
+	if _, err := take(ctx, open, "anchor", "hello-web", takeOptions{Yes: true}); err != nil {
+		t.Fatal(err)
+	}
+	reportsHolding(t, open, heldFile)
+	preview, err := converge(ctx, open, "anchor", false, "", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	saved, savedPoll := inventory.HoldWaitFor, inventory.HoldPoll
+	inventory.HoldWaitFor, inventory.HoldPoll = time.Second, 50*time.Millisecond
+	defer func() { inventory.HoldWaitFor, inventory.HoldPoll = saved, savedPoll }()
+
+	var whileFlipping error
+	sendNodes = func(context.Context, *stores, []string) error {
+		_, whileFlipping = assign(ctx, open, "anchor", "notes")
+		return nil
+	}
+	if _, err := converge(ctx, open, "anchor", true, digestIn(t, preview), ""); err != nil {
+		t.Fatal(err)
+	}
+	if !errors.Is(whileFlipping, inventory.ErrNodeBusy) {
+		t.Fatalf("an assignment landed while the node was being converged: %v", whileFlipping)
+	}
+}

cmd/mesh-controller/advisories_counted_test.go

@@ -0,0 +1,180 @@
+package main
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// **A refusal the bus said once is counted once** (novox/hq issue 402). The bus refused the controller
+// one publish at 18:52:59 UTC on 2026-10-10 and never again, yet S9 looked at the one remembered
+// advisory every half minute for the hour it is kept, and the condition said "observed 15 time(s), last
+// 13s ago" with a refusal in its evidence every 30 seconds: two of us read it as a refusal going on and
+// went looking for a missing grant. The condition counts what the bus said, with when it last said it,
+// never how often the controller looked.
+func TestARefusalSaidOnceIsCountedOnceHoweverOftenItIsLookedAt(t *testing.T) {
+	refused := time.Date(2026, 10, 10, 18, 52, 59, 0, time.UTC)
+	now := refused.Add(10 * time.Second)
+	store := conditions.NewInMemory()
+	k := conditions.NewKeeper(t.Context(), conditions.Options{Store: store, History: store,
+		Teller: &conditions.Told{}, Now: func() time.Time { return now }})
+	t.Cleanup(func() { k.Close(t.Context()) })
+
+	// The words the live condition bus.controller.refused carried on 2026-10-10.
+	said := "the bus refused the controller: nats: permissions violation: Permissions Violation for " +
+		`Publish to "mesh.seat.mesh-delivery.tool.times"`
+	advisory := link.Advisory{Kind: link.AdvisoryRefused, ID: "controller", Said: said,
+		First: refused, Last: refused, Count: 1}
+	look := func() conditions.Condition {
+		t.Helper()
+		f := &signalFacts{now: now, host: "novox", advisories: []link.Advisory{advisory}}
+		if err := k.Reconcile(t.Context(), "S9", watchAdvisories(f)); err != nil {
+			t.Fatal(err)
+		}
+		c, found, err := conditions.ReadOne(t.Context(), store, "bus.controller.refused")
+		if err != nil || !found {
+			t.Fatalf("bus.controller.refused: found %v, %v", found, err)
+		}
+		return c
+	}
+
+	var c conditions.Condition
+	for range 15 {
+		c = look()
+		now = now.Add(30 * time.Second)
+	}
+	if c.Observations != 1 || len(c.Evidence) != 1 {
+		t.Fatalf("one refusal, looked at 15 times, reads as observed %d time(s) with %d evidence lines: %+v",
+			c.Observations, len(c.Evidence), c.Evidence)
+	}
+	if !c.LastObserved.Equal(refused) || !c.Evidence[0].At.Equal(refused) {
+		t.Fatalf("last observed %s, evidence at %s: the refusal was at %s", c.LastObserved, c.Evidence[0].At, refused)
+	}
+
+	// The bus refuses it three times more between two looks: the condition counts four refusals, says
+	// the newest, and adds one line of evidence for the look that saw them.
+	again := now.Add(-5 * time.Second)
+	advisory.Last, advisory.Count = again, 4
+	c = look()
+	if c.Observations != 4 || len(c.Evidence) != 2 || !c.LastObserved.Equal(again) || !c.Evidence[0].At.Equal(again) {
+		t.Fatalf("four refusals read as observed %d time(s), last %s, evidence %+v", c.Observations, c.LastObserved, c.Evidence)
+	}
+	if !strings.Contains(c.Summary, "(4 times since 18:52 UTC)") {
+		t.Fatalf("summary %q", c.Summary)
+	}
+	now = now.Add(30 * time.Second)
+	if c = look(); c.Observations != 4 || len(c.Evidence) != 2 {
+		t.Fatalf("a look with nothing new counted: observed %d time(s), evidence %+v", c.Observations, c.Evidence)
+	}
+}
+
+// **A condition that looks at the present still counts its looks** (novox/hq issue 402 changes only
+// what reads a record): a machine silent for three looks was observed three times, and says so.
+func TestAConditionOfThePresentCountsItsLooks(t *testing.T) {
+	now := time.Date(2026, 10, 10, 19, 0, 0, 0, time.UTC)
+	store := conditions.NewInMemory()
+	k := conditions.NewKeeper(t.Context(), conditions.Options{Store: store, History: store,
+		Teller: &conditions.Told{}, Now: func() time.Time { return now }})
+	t.Cleanup(func() { k.Close(t.Context()) })
+	var c conditions.Condition
+	for range 3 {
+		var err error
+		if c, err = k.Observe(t.Context(), conditions.Observation{Scope: conditions.ScopeMachine, ID: "ace",
+			Kind: "silent", Machine: "ace", Severity: conditions.Warning, Summary: "ace has not been heard from",
+			Source: "S1"}); err != nil {
+			t.Fatal(err)
+		}
+		now = now.Add(30 * time.Second)
+	}
+	if c.Observations != 3 || len(c.Evidence) != 3 || !c.LastObserved.Equal(now.Add(-30*time.Second)) {
+		t.Fatalf("observed %d time(s), %d evidence lines, last %s", c.Observations, len(c.Evidence), c.LastObserved)
+	}
+}
+
+// **One key, one watcher** (novox/hq issue 440). A consumer's max-deliveries condition is said from
+// DEAD_LETTERS while it holds a message the consumer gave up on (issue 330). A max-deliveries advisory
+// without a token names the same key; read beside it, each look added an observation and a line of
+// evidence through the dead-letter half, and the two summaries overwrote each other on every look. The
+// dead-letter row alone says that key, and counts the messages given up on, never the looks.
+func TestAHeldDeadLetterIsCountedByWhatWasGivenUpNotByTheLooks(t *testing.T) {
+	gaveUp := time.Date(2026, 10, 10, 21, 4, 0, 0, time.UTC)
+	now := gaveUp.Add(20 * time.Second)
+	store := conditions.NewInMemory()
+	k := conditions.NewKeeper(t.Context(), conditions.Options{Store: store, History: store,
+		Teller: &conditions.Told{}, Now: func() time.Time { return now }})
+	t.Cleanup(func() { k.Close(t.Context()) })
+
+	const key = "bus.EVENTS.media_sonarr.max-deliveries"
+	held := map[string]int{"EVENTS.media_sonarr": 1}
+	newest := map[string]time.Time{"EVENTS.media_sonarr": gaveUp}
+	advisory := link.Advisory{Kind: link.AdvisoryMaxDeliveries, ID: "EVENTS.media_sonarr", Stream: "EVENTS",
+		Consumer: "media_sonarr", Said: "sonarr on media handed message 7 over 5 times and gave up on it",
+		First: gaveUp, Last: gaveUp, Count: 1}
+	look := func() conditions.Condition {
+		t.Helper()
+		f := &signalFacts{now: now, host: "novox", advisories: []link.Advisory{advisory},
+			deadLetters: held, deadLettersNewest: newest}
+		if err := k.Reconcile(t.Context(), "S9", watchAdvisories(f)); err != nil {
+			t.Fatal(err)
+		}
+		c, found, err := conditions.ReadOne(t.Context(), store, key)
+		if err != nil || !found {
+			t.Fatalf("%s: found %v, %v", key, found, err)
+		}
+		if !strings.Contains(c.Summary, "dead-letters verb") {
+			t.Fatalf("the summary is not the dead-letter row's: %q", c.Summary)
+		}
+		return c
+	}
+
+	var c conditions.Condition
+	for range 5 {
+		c = look()
+		now = now.Add(30 * time.Second)
+	}
+	if c.Observations != 1 || len(c.Evidence) != 1 || !c.LastObserved.Equal(gaveUp) {
+		t.Fatalf("one message given up on, looked at five times, reads as observed %d time(s), last %s, "+
+			"with %d evidence lines: %+v", c.Observations, c.LastObserved, len(c.Evidence), c.Evidence)
+	}
+
+	// The consumer gives up on a second message between two looks: two given up on, one more line.
+	again := now.Add(-10 * time.Second)
+	held["EVENTS.media_sonarr"], newest["EVENTS.media_sonarr"] = 2, again
+	c = look()
+	if c.Observations != 2 || len(c.Evidence) != 2 || !c.LastObserved.Equal(again) {
+		t.Fatalf("two given up on read as observed %d time(s), last %s, evidence %+v", c.Observations,
+			c.LastObserved, c.Evidence)
+	}
+	now = now.Add(30 * time.Second)
+	if c = look(); c.Observations != 2 || len(c.Evidence) != 2 {
+		t.Fatalf("a look with nothing new counted: observed %d time(s), evidence %+v", c.Observations, c.Evidence)
+	}
+}
+
+// The advisory still says the max-deliveries it alone knows: a message given up on that could not be
+// kept, under a key of its own (issue 330), which issue 440's change leaves as it was.
+func TestAMessageThatCouldNotBeKeptIsStillSaidFromTheAdvisory(t *testing.T) {
+	at := time.Date(2026, 10, 10, 21, 4, 0, 0, time.UTC)
+	f := &signalFacts{now: at, host: "novox", advisories: []link.Advisory{{Kind: link.AdvisoryMaxDeliveries,
+		ID: "EVENTS.media_sonarr", Stream: "EVENTS", Consumer: "media_sonarr", Token: link.AdvisoryNotKept,
+		Said: "sonarr on media gave up on message 7, and it could not be kept", First: at, Last: at, Count: 1}}}
+	said := watchAdvisories(f)
+	if len(said) != 1 || said[0].Key() != "bus.EVENTS.media_sonarr.not-kept" {
+		t.Fatalf("%+v", said)
+	}
+}
+
+// A max-deliveries advisory without a token names a consumer's dead-letter key, which only DEAD_LETTERS
+// says (novox/hq issues 330 and 440): with nothing held, the advisory alone raises nothing.
+func TestAMaxDeliveriesAdvisoryAloneRaisesNothing(t *testing.T) {
+	at := time.Date(2026, 10, 10, 21, 4, 0, 0, time.UTC)
+	f := &signalFacts{now: at, host: "novox", advisories: []link.Advisory{{Kind: link.AdvisoryMaxDeliveries,
+		ID: "EVENTS.media_sonarr", Stream: "EVENTS", Consumer: "media_sonarr",
+		Said: "sonarr on media handed message 7 over 5 times and gave up on it", First: at, Last: at, Count: 1}}}
+	if said := watchAdvisories(f); len(said) != 0 {
+		t.Fatalf("said %+v", said)
+	}
+}

cmd/mesh-controller/agent_account.go

@@ -0,0 +1,253 @@
+package main
+
+// The account agents run as (novox/hq ADR 0266).
+//
+// On the control node every agent session ran as the operator's account, which may become root without a
+// password — so any agent there could become root without a person, and ADR 0259 §8 (an answer from the
+// operator's phone authorises an act) rests on that being false where the router and its channels run. The
+// decision: a node may name an account its agents run as, of their own and without sudo; the operator's
+// account keeps its sudo.
+//
+//   - **Named at the controller's terminal only** (`node agent-account`): not a verb, not a setting, so no
+//     agent can name itself another account. Empty is a real state: agents run as the operator there.
+//   - **Composed** as `${machine:agent-account}`, `${machine:agent-home}` and `${machine:agent-root}` for the
+//     agent's module, which declares the account with `root: never`, and as MESH_AGENT_ACCOUNT and
+//     MESH_AGENT_HOME for its tools (catalogue/machine_into_files.go, runtime.go).
+//   - **Judged by the machine itself.** The node-engine reads, on every look, whether an account declared
+//     `root: never` can become root without a person — uid 0, a group that grants root, a sudo rule, a
+//     secret of the mesh it may read — and says it as the declaring module's account verdict, marked
+//     Root "never". agentConfined reads that verdict; the self-check (probe DA) raises
+//     `agent-can-become-root` while it does not hold, and `node show` says it.
+//
+// A verdict not given is never a pass: an engine older than the judging, an account not yet declared, a
+// statement that says nothing of it — each is "not judged", and fails.
+
+import (
+	"context"
+	"fmt"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// kindAgentCanBecomeRoot is the condition raised while a machine's agent account can become root without
+// a person, or is not judged (ADR 0266).
+const kindAgentCanBecomeRoot = "agent-can-become-root"
+
+// agentAccountProbe is the self-check's probe of it.
+const agentAccountProbe = "DA"
+
+// agentConfined says whether the agents of a machine that names an agent account are confined: the
+// machine's newest statement holds a healthy account verdict, judged for root, on that account. named is
+// false for a machine that names none — agents run as the operator account there, which this does not
+// judge. why is said either way, in the mesh's words; err is a store that could not be read.
+//
+// The one judgement: `node show`, the self-check, and ADR 0259's router honouring a verified sender read
+// it here.
+// now is the judging clock, threaded so a caller judging several things at one instant judges them all at it.
+func agentConfined(ctx context.Context, inv *inventory.Inventory, node string, now time.Time) (named, confined bool, why string, err error) {
+	n, err := inv.NodeByName(ctx, node)
+	if err != nil {
+		return false, false, "", err
+	}
+	if n.AgentAccount == "" {
+		return false, false, fmt.Sprintf("%s names no agent account: agents run as the operator account (%s)",
+			node, orNoneKnown(n.Account)), nil
+	}
+	h, had, err := inv.HealthOf(ctx, node)
+	if err != nil {
+		return true, false, "", err
+	}
+	confined, why = judgedConfined(n.AgentAccount, h, had, now)
+	return true, confined, why, nil
+}
+
+// verdictFreshFor is how old the statement holding the verdict may be, by this controller's clock. A
+// node-engine states its health on every change and at least every five minutes (mesh-host's sayAnyway), so
+// three statements missed is a node-engine stopped, or a machine away. **A stale verdict is not a pass**: an
+// agent that stopped the node-engine must not leave "cannot become root" standing from before.
+const verdictFreshFor = 15 * time.Minute
+
+// judgedConfined is the judgement over one statement, without the store, at now.
+func judgedConfined(agent string, h inventory.NodeHealth, had bool, now time.Time) (bool, string) {
+	if !had {
+		return false, fmt.Sprintf("the agent account %s is not judged: the machine's node-engine has stated "+
+			"nothing of what it runs", agent)
+	}
+	if age := now.Sub(h.HeardAt); age > verdictFreshFor {
+		return false, fmt.Sprintf("the agent account %s is not judged: the machine's newest statement was heard at "+
+			"%s, more than %d minutes ago, and a verdict that old is not a verdict on now", agent,
+			h.HeardAt.Local().Format("2006-01-02 15:04"), int(verdictFreshFor.Minutes()))
+	}
+	if h.Contract < link.RootContract {
+		return false, fmt.Sprintf("the agent account %s is not judged: the machine's node-engine is older than "+
+			"the judging of an account's root (its statement's contract is %d, the judging is %d)",
+			agent, h.Contract, link.RootContract)
+	}
+	var verdicts []inventory.ResourceHealth
+	for _, r := range h.Resources {
+		if r.Kind == link.KindAccount && r.Target == agent && r.Root == link.RootNever {
+			verdicts = append(verdicts, r)
+		}
+	}
+	if len(verdicts) == 0 {
+		return false, fmt.Sprintf("the agent account %s is not judged: the machine's newest statement holds no "+
+			"verdict on it — no module there declares it never to become root, or the declaration naming it "+
+			"has not been applied", agent)
+	}
+	sort.Slice(verdicts, func(i, j int) bool {
+		return verdicts[i].Module+verdicts[i].Resource < verdicts[j].Module+verdicts[j].Resource
+	})
+	for _, v := range verdicts {
+		switch v.State {
+		case link.StateHealthy:
+		case link.StateUnhealthy:
+			// The engine's own words, which start with link.ReasonRoot when it found a way to root.
+			return false, fmt.Sprintf("the agent account %s %s (said by %s's %s)", agent,
+				orNoneKnown(v.Reason), v.Module, v.Resource)
+		default:
+			return false, fmt.Sprintf("the agent account %s is not judged: %s (%s's %s, %s)", agent,
+				orNoneKnown(v.Reason), v.Module, v.Resource, v.State)
+		}
+	}
+	return true, fmt.Sprintf("the agent account %s cannot become root without a person (judged %s)", agent,
+		h.SaidAt.Local().Format("2006-01-02 15:04"))
+}
+
+// searchQuietFor is how long the controller lets an agent account's verdict wait for the node-engine's setuid
+// search before that is itself the urgent condition: the longest a search is expected to take (link.RootSearchQuiet,
+// the engine's own value; novox/hq issue 361 — the search runs to completion, with no bound of its own), counted
+// from when this controller first saw it waiting, never from the engine's start. Quiet raises nothing; it never
+// makes the agent account confined, which only a healthy verdict from a complete, fresh search does.
+const searchQuietFor = link.RootSearchQuiet
+
+// The kinds of an agent account's verdict, for the quiet a search earns.
+const (
+	verdictOther    = iota // anything else: a stale statement, an older engine, no verdict, another unknown
+	verdictPending         // waiting for the search, and otherwise healthy
+	verdictComplete        // judged: healthy, or a way to root found
+)
+
+// rootVerdictKind reads a statement for the agent account (novox/hq ADR 0266): pending when every verdict on it
+// is healthy or not judged yet because the engine's setuid search runs, at least one of them that; complete when
+// every verdict is healthy or one found a way to root. The engine's own "since" is not read: it starts again at
+// every restart of the engine.
+func rootVerdictKind(agent string, h inventory.NodeHealth, had bool, now time.Time) int {
+	if !had || now.Sub(h.HeardAt) > verdictFreshFor || h.Contract < link.RootContract {
+		return verdictOther
+	}
+	pending, any := false, false
+	for _, r := range h.Resources {
+		if r.Kind != link.KindAccount || r.Target != agent || r.Root != link.RootNever {
+			continue
+		}
+		any = true
+		switch {
+		case r.State == link.StateHealthy:
+		case r.State == link.StateUnhealthy:
+			return verdictComplete
+		case r.State == link.StateUnknown && strings.HasPrefix(r.Reason, link.ReasonRootPending):
+			pending = true
+		default:
+			return verdictOther
+		}
+	}
+	switch {
+	case !any:
+		return verdictOther
+	case pending:
+		return verdictPending
+	}
+	return verdictComplete
+}
+
+// searchStillRunning says the one thing keeping an agent account from being judged is the node-engine's setuid
+// search, and that this controller first saw it waiting less than searchQuietFor ago — kept in the store, so a
+// node-engine restarted in a loop does not keep it quiet. A complete verdict forgets when it began.
+func searchStillRunning(ctx context.Context, inv *inventory.Inventory, node, agent string, h inventory.NodeHealth,
+	had bool, now time.Time) (bool, error) {
+	switch rootVerdictKind(agent, h, had, now) {
+	case verdictComplete:
+		return false, inv.RootSearchJudged(ctx, node)
+	case verdictPending:
+		since, err := inv.RootSearchPending(ctx, node, now)
+		if err != nil {
+			return false, err
+		}
+		return now.Sub(since) <= searchQuietFor, nil
+	}
+	return false, nil
+}
+
+// probeAgentAccounts is DA: every machine that names an agent account has it judged, on its node-engine's
+// newest statement, unable to become root without a person (ADR 0266).
+func probeAgentAccounts(ctx context.Context, d *doctor) ([]conditions.Observation, error) {
+	inv := d.open.inventory
+	nodes, err := inv.Nodes(ctx)
+	if err != nil {
+		return nil, err
+	}
+	var out []conditions.Observation
+	for _, n := range nodes {
+		if n.AgentAccount == "" {
+			continue
+		}
+		h, had, err := inv.HealthOf(ctx, n.Name)
+		if err != nil {
+			return nil, err
+		}
+		now := time.Now()
+		quiet, err := searchStillRunning(ctx, inv, n.Name, n.AgentAccount, h, had, now)
+		if err != nil {
+			return nil, err
+		}
+		confined, why := judgedConfined(n.AgentAccount, h, had, now)
+		if confined {
+			continue
+		}
+		// Not judged yet only because the node-engine's search runs and no complete, fresh one judges: not the
+		// urgent condition after every restart. The agent is still not confined — ADR 0259's router reads
+		// agentConfined, not this — and `node show` still says not judged. Loud again once the search fails,
+		// waits past searchQuietFor, or the statement goes stale.
+		if quiet {
+			continue
+		}
+		out = append(out, conditions.Observation{Scope: conditions.ScopeMachine, ID: n.Name, Token: "agent-root",
+			Machine: n.Name, Severity: conditions.Urgent,
+			Summary: fmt.Sprintf("on %s, %s (ADR 0266): an agent there may become root without a person, and "+
+				"no answer from a channel authorises an act there (ADR 0259 §8)", n.Name, why),
+			Said: why})
+	}
+	return sortedFound(out), nil
+}
+
+// agentAccountLines is what `node show` says of the account agents run as.
+func agentAccountLines(ctx context.Context, inv *inventory.Inventory, n inventory.Node) []string {
+	if n.AgentAccount == "" {
+		return []string{fmt.Sprintf("  agents run as      the operator account (%s); no agent account is named",
+			orNoneKnown(n.Account))}
+	}
+	_, confined, why, err := agentConfined(ctx, inv, n.Name, time.Now())
+	if err != nil {
+		return []string{fmt.Sprintf("  agents run as      %s (home %s); whether it can become root could NOT be read: %v",
+			n.AgentAccount, n.AgentHome(), err)}
+	}
+	verdict := "CAN become root, or is not judged: " + why
+	if confined {
+		verdict = why
+	}
+	return []string{fmt.Sprintf("  agents run as      %s (home %s)", n.AgentAccount, n.AgentHome()),
+		"                     " + verdict}
+}
+
+// orNoneKnown is a value, or that none is known.
+func orNoneKnown(s string) string {
+	if strings.TrimSpace(s) == "" {
+		return "none known"
+	}
+	return s
+}

cmd/mesh-controller/agent_account_integration_test.go

@@ -0,0 +1,161 @@
+//go:build integration
+
+package main
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	snapshot "github.com/novox/mesh-controller/internal/facts"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+	"github.com/novox/mesh-host/rootsearch"
+)
+
+func TestTheSelfCheckSaysAnAgentAccountThatCanBecomeRoot(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	inv := open.inventory
+	for _, n := range []string{"anchor", "laptop"} {
+		if _, err := inv.NodeByName(ctx, n); err != nil {
+			if _, err := inv.AddNode(ctx, n); err != nil {
+				t.Fatal(err)
+			}
+		}
+		if err := inv.SetAccount(ctx, n, "ops", ""); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if err := inv.SetAgentAccount(ctx, "anchor", "agent", ""); err != nil {
+		t.Fatal(err)
+	}
+	d := &doctor{open: open}
+	found, err := probeAgentAccounts(ctx, d)
+	if err != nil {
+		t.Fatal(err)
+	}
+	found = onlyMachine(found, "anchor")
+	if len(found) != 1 || found[0].Machine != "anchor" || found[0].Severity != conditions.Urgent ||
+		!strings.Contains(found[0].Said, "not judged") {
+		t.Fatalf("a named agent account with no verdict: %+v", found)
+	}
+	w := plainWordings[kindAgentCanBecomeRoot](conditions.Observation{Kind: kindAgentCanBecomeRoot, Machine: "anchor"})
+	if w.Headline == "" || w.Needs == "" || w.Resolved == "" {
+		t.Errorf("the condition has no plain words: %+v", w)
+	}
+
+	healthy := inventory.ResourceHealth{Module: "claude-code", Resource: "claude-code.agent-account",
+		Kind: link.KindAccount, Target: "agent", State: link.StateHealthy, Root: link.RootNever, Account: "agent"}
+	if _, err := inv.RecordHealth(ctx, inventory.NodeHealth{Node: "anchor", Contract: link.RootContract,
+		SaidAt: time.Now(), HeardAt: time.Now(), Resources: []inventory.ResourceHealth{healthy}}); err != nil {
+		t.Fatal(err)
+	}
+	if found, err = probeAgentAccounts(ctx, d); err != nil || len(onlyMachine(found, "anchor")) != 0 {
+		t.Fatalf("a judged agent account still fails: %+v %v", found, err)
+	}
+	if named, confined, why, err := agentConfined(ctx, inv, "anchor", time.Now()); err != nil || !named || !confined {
+		t.Fatalf("agentConfined on anchor: %v %v %q %v", named, confined, why, err)
+	}
+	if named, _, why, err := agentConfined(ctx, inv, "laptop", time.Now()); err != nil || named ||
+		!strings.Contains(why, "operator account") {
+		t.Fatalf("agentConfined on a machine naming none: %v %q %v", named, why, err)
+	}
+}
+
+func TestTheFactsCarryTheAgentAccountAsAPseudonym(t *testing.T) {
+	open, _ := aMeshWithSecrets(t)
+	ctx := t.Context()
+	if err := open.inventory.SetAccount(ctx, "anchor", "keeper", ""); err != nil {
+		t.Fatal(err)
+	}
+	if err := open.inventory.SetAgentAccount(ctx, "anchor", "warden", ""); err != nil {
+		t.Fatal(err)
+	}
+	f, err := gatherFacts(ctx, open, "2.11.17")
+	if err != nil {
+		t.Fatal(err)
+	}
+	body, _ := f.Encode()
+	if strings.Contains(string(body), "warden") {
+		t.Error("the agent account's name is in the snapshot")
+	}
+	m, ok := f.Machine(snapshot.Pseudonym("machine", "anchor"))
+	if !ok || m.AgentAccount != snapshot.Pseudonym("account", "warden") || m.Account == m.AgentAccount {
+		t.Fatalf("the anchor's agent account reads as %q (operator %q)", m.AgentAccount, m.Account)
+	}
+}
+
+func TestASearchStillRunningAfterARestartIsNotUrgent(t *testing.T) {
+	if searchQuietFor != rootsearch.Quiet {
+		t.Fatalf("the quiet is %s and the node-engine's %s: they are one value", searchQuietFor, rootsearch.Quiet)
+	}
+	// A daily search that finishes within the quiet never leaves the account unjudged between two of them.
+	if rootsearch.FreshFor < rootsearch.Every+rootsearch.Quiet {
+		t.Fatalf("a complete search judges for %s, less than a day's search (%s) and the quiet (%s)",
+			rootsearch.FreshFor, rootsearch.Every, rootsearch.Quiet)
+	}
+	open := aMesh(t)
+	ctx := t.Context()
+	inv := open.inventory
+	if _, err := inv.NodeByName(ctx, "anchor"); err != nil {
+		if _, err := inv.AddNode(ctx, "anchor"); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if err := inv.SetAgentAccount(ctx, "anchor", "agent", ""); err != nil {
+		t.Fatal(err)
+	}
+	d := &doctor{open: open}
+	say := func(state, reason string) []conditions.Observation {
+		t.Helper()
+		// The engine's since is always now: it was just restarted.
+		v := inventory.ResourceHealth{Module: "claude-code", Resource: "claude-code.agent-account",
+			Kind: link.KindAccount, Target: "agent", State: state, Reason: reason, Root: link.RootNever,
+			Account: "agent", Since: time.Now()}
+		if _, err := inv.RecordHealth(ctx, inventory.NodeHealth{Node: "anchor", Contract: link.RootContract,
+			SaidAt: time.Now(), HeardAt: time.Now(), Resources: []inventory.ResourceHealth{v}}); err != nil {
+			t.Fatal(err)
+		}
+		found, err := probeAgentAccounts(ctx, d)
+		if err != nil {
+			t.Fatal(err)
+		}
+		return onlyMachine(found, "anchor")
+	}
+	running := link.ReasonRootPending + ": the search for setuid programs, started at 19:21, has not finished yet"
+	healthy := func() {
+		t.Helper()
+		if found := say(link.StateHealthy, ""); len(found) != 0 {
+			t.Fatalf("a healthy verdict raised: %+v", found)
+		}
+	}
+	if found := say(link.StateUnknown, running); len(found) != 0 {
+		t.Fatalf("a search first seen now was raised: %+v", found)
+	}
+	if _, confined, why, _ := agentConfined(ctx, inv, "anchor", time.Now()); confined || !strings.Contains(why, "not judged") {
+		t.Fatalf("an account whose search runs was read as confined: %q", why)
+	}
+	// The engine restarted again and again, each statement's own since fresh: the controller's clock runs on.
+	if _, err := inv.RootSearchPending(ctx, "anchor", time.Now().Add(-searchQuietFor-time.Minute)); err != nil {
+		t.Fatal(err)
+	}
+	healthy() // a complete verdict forgets when the waiting began …
+	if _, err := inv.RootSearchPending(ctx, "anchor", time.Now().Add(-searchQuietFor-time.Minute)); err != nil {
+		t.Fatal(err) // … and this restart loop began past the bound
+	}
+	if found := say(link.StateUnknown, running); len(found) != 1 || found[0].Severity != conditions.Urgent {
+		t.Fatalf("a search pending past the bound, by the controller's clock, was not urgent: %+v", found)
+	}
+	healthy()
+	incomplete := rootsearch.ReasonIncomplete + ": the search for setuid programs did not finish (last tried at " +
+		"19:23: timeout); it is tried again later"
+	if found := say(link.StateUnknown, incomplete); len(found) != 1 || found[0].Severity != conditions.Urgent {
+		t.Fatalf("a search that did not finish was not urgent: %+v", found)
+	}
+	if found := say(link.StateUnhealthy, link.ReasonRoot+": in the group docker; "+running); len(found) != 1 ||
+		found[0].Severity != conditions.Urgent {
+		t.Fatalf("a way to root found while the search runs was not urgent: %+v", found)
+	}
+}

cmd/mesh-controller/agent_account_test.go

@@ -0,0 +1,134 @@
+package main
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// The agent account's judgement (novox/hq ADR 0266): confined only on a healthy account verdict judged for
+// root, on the very account; every verdict not given — no statement, an older engine, no verdict on it, a
+// verdict of unknown — is "not judged" and fails, never a pass.
+func TestAnAgentAccountIsConfinedOnlyOnAHealthyVerdictJudgedForRoot(t *testing.T) {
+	at := time.Date(2026, 10, 8, 19, 21, 0, 0, time.UTC)
+	verdict := func(target, root, state, reason string) inventory.ResourceHealth {
+		return inventory.ResourceHealth{Module: "claude-code", Resource: "claude-code.agent-account",
+			Kind: link.KindAccount, Target: target, State: state, Reason: reason, Root: root, Account: target}
+	}
+	statement := func(contract int, rs ...inventory.ResourceHealth) inventory.NodeHealth {
+		return inventory.NodeHealth{Node: "anchor", Contract: contract, SaidAt: at, HeardAt: at, Resources: rs}
+	}
+	for _, c := range []struct {
+		name     string
+		h        inventory.NodeHealth
+		had      bool
+		confined bool
+		says     string
+	}{
+		{"judged and unable", statement(link.RootContract, verdict("agent", link.RootNever, link.StateHealthy, "")),
+			true, true, "cannot become root without a person"},
+		{"judged and able", statement(link.RootContract, verdict("agent", link.RootNever, link.StateUnhealthy,
+			link.ReasonRoot+": in the group docker, which grants root")), true, false, "in the group docker"},
+		{"a verdict of unknown", statement(link.RootContract, verdict("agent", link.RootNever, link.StateUnknown,
+			"sudo could not be read")), true, false, "not judged"},
+		{"no statement", inventory.NodeHealth{}, false, false, "not judged"},
+		{"an older engine", statement(link.ReadinessContract, verdict("agent", "", link.StateHealthy, "")),
+			true, false, "older than the judging"},
+		{"a verdict on groups only", statement(link.RootContract, verdict("agent", "", link.StateHealthy, "")),
+			true, false, "no verdict on it"},
+		{"a verdict on another account", statement(link.RootContract, verdict("ops", link.RootNever, link.StateHealthy, "")),
+			true, false, "no verdict on it"},
+	} {
+		confined, why := judgedConfined("agent", c.h, c.had, at.Add(time.Minute))
+		if confined != c.confined || !strings.Contains(why, c.says) {
+			t.Errorf("%s: confined %v, %q; want %v saying %q", c.name, confined, why, c.confined, c.says)
+		}
+	}
+	// A verdict heard longer ago than the bound is no verdict: an agent that stopped the node-engine must not
+	// leave "healthy" standing.
+	fresh := statement(link.RootContract, verdict("agent", link.RootNever, link.StateHealthy, ""))
+	if ok, _ := judgedConfined("agent", fresh, true, at.Add(verdictFreshFor)); !ok {
+		t.Error("a verdict exactly at the bound is still one")
+	}
+	if ok, why := judgedConfined("agent", fresh, true, at.Add(verdictFreshFor+time.Second)); ok ||
+		!strings.Contains(why, "not judged") {
+		t.Errorf("a stale healthy verdict passed: %q", why)
+	}
+}
+
+// DA raises an urgent condition, with plain words, on a machine whose agent account is not judged unable to
+// become root; a machine that names none is not its to judge.
+
+func TestTheAgentRootWordsArePlain(t *testing.T) {
+	w := plainWordings[kindAgentCanBecomeRoot](conditions.Observation{Kind: kindAgentCanBecomeRoot, Machine: "anchor"})
+	if why, ok := conditions.PlainWords(w, "anchor"); !ok {
+		t.Fatalf("not plain: %s: %+v", why, w)
+	}
+}
+
+func onlyMachine(obs []conditions.Observation, machine string) []conditions.Observation {
+	var out []conditions.Observation
+	for _, o := range obs {
+		if o.Machine == machine {
+			out = append(out, o)
+		}
+	}
+	return out
+}
+
+// The snapshot a merge check composes from carries the agent account as a pseudonym (novox/hq ADR 0266),
+// so a change is judged against machines that name one, and the name never leaves.
+
+// No verb runs a `node` command that sets something: through the generic `command` verb, `node account`,
+// `node agent-account` and every other `node` subcommand but list and show are refused, naming the terminal.
+func TestNoVerbSetsANodesAccounts(t *testing.T) {
+	for _, line := range []string{
+		"node agent-account novox --clear",
+		"node agent-account novox ops",
+		"node account novox agent",
+		"node account novox",
+		"node add intruder",
+		"node public-domain novox --clear",
+		"node",
+		"node frobnicate",
+	} {
+		argv, err := argvFor("command", map[string]any{"command": line})
+		if err == nil || !strings.Contains(err.Error(), "controller's terminal") ||
+			!strings.Contains(err.Error(), "ADR 0266") {
+			t.Errorf("%q ran as %v (%v); want a refusal naming the terminal", line, argv, err)
+		}
+	}
+	for _, line := range []string{"node show novox", "node list --json", "status --json"} {
+		if _, err := argvFor("command", map[string]any{"command": line}); err != nil {
+			t.Errorf("%q, a read, was refused: %v", line, err)
+		}
+	}
+	if err := terminalOnly([]string{"node", "account", "a", "b"}); err == nil {
+		t.Error("the refusal is not only the command verb's")
+	}
+}
+
+// Naming the agent account is the controller's terminal's alone: the `node` verb only shows.
+func TestTheNodeVerbOnlyShows(t *testing.T) {
+	argv, err := argvFor("node", map[string]any{"node": "anchor"})
+	if err != nil || strings.Join(argv, " ") != "node show anchor" {
+		t.Fatalf("the node verb runs %v (%v)", argv, err)
+	}
+	for _, v := range catalogue.ControllerVerbs {
+		if strings.Contains(v.Name, "agent") {
+			t.Errorf("a verb %q may name the agent account", v.Name)
+		}
+	}
+}
+
+// Until a complete search for setuid programs judges — none since the node-engine's state was kept, or the last
+// older than the engine lets one judge — the agent account is not judged, and the search runs to its end with no
+// bound (novox/hq issue 361). DA does not raise that as urgent within searchQuietFor, counted from when this
+// controller first saw it waiting — never from the engine's own "since", which a restart resets, so an engine
+// restarted in a loop does not keep it quiet. The account is still not confined, and `node show` still says not
+// judged; a search that failed, or a way to root found, is urgent at once.

cmd/mesh-controller/api.go

@@ -94,19 +94,29 @@ func (n notYet) Who(*http.Request) (string, error) {
 func commands(who Authenticator) http.Handler {
 	mux := http.NewServeMux()
 
-	mux.HandleFunc("POST /assign", acting(who, func(ctx context.Context, open *stores, in request) (string, error) {
-		return assign(ctx, open, in.Node, in.Module)
+	mux.HandleFunc("POST /assign", acting(who, true, func(ctx context.Context, open *stores, in request) (string, error) {
+		return assign(ctx, open, in.Node, splitModules(in.Module)...)
 	}))
-	mux.HandleFunc("POST /unassign", acting(who, func(ctx context.Context, open *stores, in request) (string, error) {
-		return unassign(ctx, open, in.Node, in.Module)
+	mux.HandleFunc("POST /unassign", acting(who, true, func(ctx context.Context, open *stores, in request) (string, error) {
+		return unassign(ctx, open, in.Node, splitModules(in.Module)...)
+	}))
+	// Adoption (novox/hq ADR 0100): the same acts as `take`, `converge` and `adopt`.
+	mux.HandleFunc("POST /take", acting(who, true, func(ctx context.Context, open *stores, in request) (string, error) {
+		return take(ctx, open, in.Node, in.Module, takeOptions{Yes: in.Yes, Digest: in.Digest})
+	}))
+	mux.HandleFunc("POST /converge", acting(who, false, func(ctx context.Context, open *stores, in request) (string, error) {
+		return converge(ctx, open, in.Node, in.Yes, in.Digest, in.Filter)
+	}))
+	mux.HandleFunc("POST /adopt", acting(who, false, func(ctx context.Context, open *stores, in request) (string, error) {
+		return adopt(ctx, open, in.Node)
 	}))
 
 	// Anything else is said plainly, because a command surface answering 404 to a verb somebody
 	// expected is indistinguishable from one that is down.
 	mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
 		refuse(w, http.StatusNotFound, fmt.Errorf(
-			"%s %s is not something this mesh can be asked; it accepts POST /assign and "+
-				"POST /unassign", r.Method, r.URL.Path))
+			"%s %s is not something this mesh can be asked; it accepts POST /assign, "+
+				"POST /unassign, POST /take, POST /converge and POST /adopt", r.Method, r.URL.Path))
 	})
 	return mux
 }
@@ -114,11 +124,17 @@ func commands(who Authenticator) http.Handler {
 type request struct {
 	Node   string `json:"node"`
 	Module string `json:"module"`
+	// Yes, Digest and Filter are converge's and take's: do it rather than preview it, the digest
+	// of the preview it acts on, and (converge) which module loads the mesh's filter.
+	Yes    bool   `json:"yes,omitempty"`
+	Digest string `json:"digest,omitempty"`
+	Filter string `json:"filter,omitempty"`
 }
 
 // acting is the shape every route shares: authenticate, read, act, answer.
 func acting(
 	who Authenticator,
+	needsModule bool,
 	do func(context.Context, *stores, request) (string, error),
 ) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
@@ -131,8 +147,12 @@ func acting(
 			refuse(w, http.StatusBadRequest, fmt.Errorf("this is not a request this understands: %w", err))
 			return
 		}
-		if in.Node == "" || in.Module == "" {
-			refuse(w, http.StatusBadRequest, errors.New(`both "node" and "module" are needed`))
+		if in.Node == "" || (needsModule && in.Module == "") {
+			if needsModule {
+				refuse(w, http.StatusBadRequest, errors.New(`both "node" and "module" are needed`))
+			} else {
+				refuse(w, http.StatusBadRequest, errors.New(`"node" is needed`))
+			}
 			return
 		}
 

cmd/mesh-controller/api_test.go

@@ -1,3 +1,5 @@
+//go:build integration
+
 package main
 
 import (

cmd/mesh-controller/apply_failing.go

@@ -0,0 +1,164 @@
+package main
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// kindApplyFailing is S21's kind: a machine whose declarations have been refused, or applied only in part,
+// for longer than one apply interval (novox/hq issue 233).
+const kindApplyFailing = "apply-failing"
+
+// applyEvery is how often a node-engine applies what it was last told when nothing new arrives: its
+// ReconcileEvery. A failure still there after one more of them is not one the next apply clears.
+const applyEvery = 5 * time.Minute
+
+// packageManagerKey is how a node-engine names a package manager that does not answer among what failed
+// (mesh-host's probe.go): "the package manager (pacman)".
+const packageManagerKey = "the package manager ("
+
+// watchApplyFailing is S21: **a machine that does not apply what it was sent is said by the mesh, not only
+// to someone who asks for `status`** (novox/hq issue 233, issue 187's family). A workstation refused every
+// declaration for an hour and a half because its package manager did not answer, and the mesh's only word
+// on it was a line in `status`. Raised once the machine's first report of this failure is older than one apply
+// interval **while the machine is heard** — judged by time, not by how many reports said it: a node-engine
+// says a re-apply only when how it went changed, so the same failure is one report however long it lasts.
+// Names the refusal's or the failure's words; cleared by the clean apply the node-engine then says. Not while
+// the machine is silent, asleep or not known: S1 says silent, and asleep is not lost.
+func watchApplyFailing(f *signalFacts) []conditions.Observation {
+	heard := map[string]bool{}
+	for _, m := range f.machines {
+		if !m.asleep() && !m.lastHeard.IsZero() && !m.silent(f.now) {
+			heard[m.name] = true
+		}
+	}
+	var out []conditions.Observation
+	said := map[string]bool{}
+	for _, d := range f.doing {
+		if !d.Wrong() || d.Since == nil || f.now.Sub(*d.Since) <= applyEvery || !heard[d.Node] {
+			continue
+		}
+		out = append(out, applyFailing(d, f.now))
+		said[d.Node] = true
+	}
+	// **A module's files the provisioner failed to place are a failed apply too** (novox/hq ADR 0362 §3): its client's
+	// newest word, judged by the same bound — the client says a failure once, and fills again on every change —
+	// on a machine whose node-engine applied what it was sent.
+	failed := map[string][]inventory.ProvReport{}
+	for _, r := range f.provFailed {
+		if r.Status != inventory.ProvFailed || f.now.Sub(r.At) <= applyEvery || !heard[r.Node] || said[r.Node] {
+			continue
+		}
+		failed[r.Node] = append(failed[r.Node], r)
+	}
+	for _, node := range sortedNames(failed) {
+		out = append(out, provisioningFailing(node, failed[node], f.now))
+	}
+	return out
+}
+
+// provisioningFailing is one machine's S21 condition for the modules whose files its provisioner client failed to
+// place.
+func provisioningFailing(m string, failed []inventory.ProvReport, now time.Time) conditions.Observation {
+	sort.Slice(failed, func(a, b int) bool { return failed[a].Module < failed[b].Module })
+	var names, words []string
+	since := failed[0].At
+	for _, r := range failed {
+		names = append(names, r.Module)
+		words = append(words, r.Module+": "+oneLine(orNoReason(r.Reason)))
+		if r.At.Before(since) {
+			since = r.At
+		}
+	}
+	o := conditions.Observation{Scope: conditions.ScopeMachine, ID: m, Kind: kindApplyFailing, Machine: m,
+		Severity: conditions.Warning, Said: strings.Join(words, "; "),
+		Resolved: m + " applies what it is sent again"}
+	o.Summary = fmt.Sprintf("%s's provisioner has failed to place the files of %s since %s (bound %s)", m,
+		strings.Join(names, ", "), since.UTC().Format("2006-01-02 15:04 MST"), ago(applyEvery))
+	o.Headline = m + " is not applying its update"
+	o.Explanation = fmt.Sprintf("The provisioner on %s has not been able to write the files of %s for %s. The "+
+		"details say why.", m, strings.Join(names, ", "), humanDuration(now.Sub(since)))
+	return o
+}
+
+func orNoReason(s string) string {
+	if s == "" {
+		return "no reason given"
+	}
+	return s
+}
+
+// applyFailing is one machine's S21 condition.
+func applyFailing(d inventory.Doing, now time.Time) conditions.Observation {
+	m := d.Node
+	since := d.Since.UTC().Format("2006-01-02 15:04 MST")
+	o := conditions.Observation{Scope: conditions.ScopeMachine, ID: m, Kind: kindApplyFailing, Machine: m,
+		Severity: conditions.Warning, Said: doingWords(d),
+		Resolved: m + " applies what it is sent again"}
+	how := "refused its declaration whole"
+	if d.Outcome != inventory.OutcomeRefused {
+		how = "applied its declaration only in part"
+	}
+	o.Summary = fmt.Sprintf("%s has %s since %s (bound %s): %s", m, how, since, ago(applyEvery), failedNames(d))
+	o.Headline = m + " is not applying its update"
+	o.Explanation = fmt.Sprintf("%s has %s for %s, and trying again has not helped. The details say what fails.",
+		m, plainHow(d), humanDuration(now.Sub(*d.Since)))
+	if tool := unansweringTool(d); tool != "" {
+		o.Summary = fmt.Sprintf("%s: %s does not answer, so no package reaches it; everything else it was sent "+
+			"is applied, since %s (bound %s)", m, tool, since, ago(applyEvery))
+		o.Headline = fmt.Sprintf("%s cannot install packages", m)
+		o.Explanation = fmt.Sprintf("The package manager on %s (%s) has not answered for %s, so no package reaches "+
+			"it. Everything else is still applied, so an update that repairs it can land; if none does, it needs a "+
+			"look on the machine.", m, tool, humanDuration(now.Sub(*d.Since)))
+	}
+	return o
+}
+
+// plainHow is how a machine failed, as the operator reads it.
+func plainHow(d inventory.Doing) string {
+	if d.Outcome == inventory.OutcomeRefused {
+		return "refused every update"
+	}
+	return "applied its updates only in part"
+}
+
+// unansweringTool is the package manager a machine said does not answer, or "".
+func unansweringTool(d inventory.Doing) string {
+	for _, r := range d.Failed {
+		if rest, ok := strings.CutPrefix(r.ID, packageManagerKey); ok {
+			return strings.TrimSuffix(rest, ")")
+		}
+	}
+	return ""
+}
+
+// failedNames is what failed, by name: the refusal, or the failed resources' ids.
+func failedNames(d inventory.Doing) string {
+	if d.Outcome == inventory.OutcomeRefused {
+		return "refused"
+	}
+	ids := make([]string, 0, len(d.Failed))
+	for _, r := range d.Failed {
+		ids = append(ids, r.ID)
+	}
+	sort.Strings(ids)
+	return "failed " + strings.Join(ids, ", ")
+}
+
+// doingWords is the machine's own words on what failed: the evidence, kept inside the mesh.
+func doingWords(d inventory.Doing) string {
+	if d.Outcome == inventory.OutcomeRefused {
+		return "refused: " + oneLine(d.Refused)
+	}
+	var parts []string
+	for _, r := range d.Failed {
+		parts = append(parts, r.ID+": "+oneLine(r.Error))
+	}
+	sort.Strings(parts)
+	return strings.Join(parts, "; ")
+}

cmd/mesh-controller/apply_failing_test.go

@@ -0,0 +1,123 @@
+package main
+
+import (
+	"context"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// unansweringPackageManager is anchor's last report as the workstation's read on 2026-10-04, once its
+// node-engine applies the rest (novox/hq issue 233): the package failed and the package manager did not answer,
+// the same failure on times reports since for before now.
+func unansweringPackageManager(now time.Time, forHowLong time.Duration, times int) inventory.Doing {
+	since := now.Add(-forHowLong)
+	return inventory.Doing{Node: "anchor", Outcome: inventory.OutcomeFailed, At: now.Add(-time.Second),
+		Since: &since, Times: times, Applied: 41, Failed: []inventory.FailedResource{
+			{ID: "apply", Error: `applying "pacman.base": nothing can be said about "base": this is the arch host and ` +
+				"pacman does not answer here. Either this machine is not Arch, or its package database is broken: " +
+				"pacman exited 1: error: config file /etc/pacman.conf could not be read: No such file or directory"},
+			{ID: "the package manager (pacman)", Error: "pacman does not answer here, so every package in this " +
+				"declaration fails and the rest of it is applied (novox/hq issue 233): pacman exited 1: error: config " +
+				"file /etc/pacman.conf could not be read: No such file or directory"}}}
+}
+
+// **A machine whose package manager does not answer is raised by the mesh itself, naming the tool and the
+// probe's words** (novox/hq issue 233): the words in the evidence, the path kept out of the summary.
+func TestAPackageManagerThatDoesNotAnswerIsRaisedNamingItsWords(t *testing.T) {
+	now := time.Date(2026, 10, 4, 14, 0, 0, 0, time.UTC)
+	f := calm(now)
+	f.doing = []inventory.Doing{unansweringPackageManager(now, 90*time.Minute, 18)}
+	got := watchApplyFailing(f)
+	if len(got) != 1 {
+		t.Fatalf("raised %d conditions, want one: %+v", len(got), got)
+	}
+	o := got[0]
+	if o.Key() != "machine.anchor.apply-failing" || o.Machine != "anchor" {
+		t.Errorf("the condition is not the machine's: %s", o.Key())
+	}
+	if !strings.Contains(o.Summary, "pacman does not answer") || !strings.Contains(o.Summary, "since 2026-10-04 12:30") {
+		t.Errorf("the summary does not name the tool and since when: %s", o.Summary)
+	}
+	if strings.Contains(o.Summary, "/etc/") {
+		t.Errorf("the summary carries a path, which belongs in the evidence: %s", o.Summary)
+	}
+	if !strings.Contains(o.Said, "could not be read") {
+		t.Errorf("the evidence does not carry the probe's words: %s", o.Said)
+	}
+	if !strings.Contains(o.Headline, "cannot install packages") || o.Explanation == "" || o.Resolved == "" {
+		t.Errorf("the plain words do not say it: %+v", o)
+	}
+}
+
+// **A whole refusal is raised too**, with the node-engine's words: what the workstation's report said before the
+// node-engine applied the rest.
+func TestARefusalThatGoesOnIsRaised(t *testing.T) {
+	now := time.Date(2026, 10, 4, 14, 0, 0, 0, time.UTC)
+	since := now.Add(-time.Hour)
+	f := calm(now)
+	f.doing = []inventory.Doing{{Node: "anchor", Outcome: inventory.OutcomeRefused, Since: &since, Times: 12,
+		Refused: "this is the arch host and pacman does not answer here", At: now.Add(-time.Minute)}}
+	got := watchApplyFailing(f)
+	if len(got) != 1 || !strings.Contains(got[0].Summary, "refused its declaration whole") ||
+		!strings.Contains(got[0].Said, "pacman does not answer") {
+		t.Fatalf("a refusal that went on for an hour was not raised with its words: %+v", got)
+	}
+}
+
+// **Judged by time while the machine is heard, not by how many reports said it** (review of novox/hq issue 233):
+// a node-engine says the same failure once, so one report an apply interval old is a fault that goes on; one
+// younger is not yet; and a silent or sleeping machine is S1's.
+func TestOneReportOlderThanAnApplyIsRaisedAndAQuietMachineIsNot(t *testing.T) {
+	now := time.Date(2026, 10, 4, 14, 0, 0, 0, time.UTC)
+	f := calm(now)
+	f.doing = []inventory.Doing{unansweringPackageManager(now, 6*time.Minute, 1)}
+	if got := watchApplyFailing(f); len(got) != 1 {
+		t.Errorf("one report of a failure six minutes old was not raised: %+v", got)
+	}
+	f.doing = []inventory.Doing{unansweringPackageManager(now, 4*time.Minute, 1)}
+	if got := watchApplyFailing(f); len(got) != 0 {
+		t.Errorf("a failure four minutes old was raised before one apply could clear it: %+v", got)
+	}
+	f.doing = []inventory.Doing{unansweringPackageManager(now, time.Hour, 1)}
+	f.machines[0].lastHeard = now.Add(-time.Hour)
+	if got := watchApplyFailing(f); len(got) != 0 {
+		t.Errorf("a silent machine was raised for its last report: %+v", got)
+	}
+	f = calm(now)
+	f.doing = []inventory.Doing{unansweringPackageManager(now, time.Hour, 1)}
+	f.doing[0].Node = "a-machine-the-mesh-does-not-know"
+	if got := watchApplyFailing(f); len(got) != 0 {
+		t.Errorf("a machine not heard of was raised: %+v", got)
+	}
+}
+
+// **A failed re-apply followed by a clean one clears S21** (review of novox/hq issue 233): the node-engine says
+// the clean re-apply, the store keeps it as applied with no failure since, and the condition the failure raised
+// is cleared through the keeper on the next tick.
+func TestACleanReapplyAfterAFailedOneClearsTheCondition(t *testing.T) {
+	now := time.Date(2026, 10, 4, 14, 0, 0, 0, time.UTC)
+	store := conditions.NewInMemory()
+	k := conditions.NewKeeper(t.Context(), conditions.Options{Store: store, History: store,
+		Teller: &conditions.Told{}, Now: func() time.Time { return now }})
+	defer k.Close(context.Background())
+	w := &watchdogs{keeper: k, started: now.Add(-time.Hour)}
+
+	failing := calm(now)
+	failing.doing = []inventory.Doing{unansweringPackageManager(now, 20*time.Minute, 1)}
+	w.see(t.Context(), failing)
+	open, err := k.Open(t.Context())
+	if err != nil || len(open) != 1 || open[0].Kind != kindApplyFailing {
+		t.Fatalf("the failed re-apply raised %+v (%v), want apply-failing", open, err)
+	}
+
+	clean := calm(now.Add(5 * time.Minute))
+	clean.doing = nil // the clean re-apply recorded: NotDoingWhatTheyWereTold no longer lists the machine
+	w.see(t.Context(), clean)
+	if open, _ := k.Open(t.Context()); len(open) != 0 {
+		t.Fatalf("the condition stayed open after the clean re-apply: %+v", open)
+	}
+}

cmd/mesh-controller/ask.go

@@ -0,0 +1,62 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"flag"
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// ask calls one of a module's tools, through the control plane's own broker connection.
+//
+// A module serves tools under an account scoped to exactly that (novox/hq ADR 0047), and nothing
+// else in the mesh held an account that could ask one — not an operator at a terminal, not an agent
+// acting for one (novox/hq 04-ISSUES/049). The control plane does, so it is the way in: one
+// process, one connection, one place a question can be seen to have been asked (ADR 0095).
+func askCommand(ctx context.Context, args []string) error {
+	positionals, flags := split(args)
+	set := flag.NewFlagSet("ask", flag.ContinueOnError)
+	wait := set.Duration("wait", 60*time.Second, "how long to wait for the module's answer")
+	if err := set.Parse(flags); err != nil {
+		return err
+	}
+	if len(positionals) < 2 || len(positionals) > 3 {
+		return errors.New("ask <module> <tool> [json arguments] [--wait 60s]")
+	}
+	module, tool := positionals[0], positionals[1]
+	var arguments json.RawMessage
+	if len(positionals) == 3 {
+		if !json.Valid([]byte(positionals[2])) {
+			return fmt.Errorf("the arguments are not JSON: %s", positionals[2])
+		}
+		arguments = json.RawMessage(positionals[2])
+	}
+
+	server, err := connectLink(ctx, nil, nil, nil)
+	if err != nil {
+		return err
+	}
+	defer server.Close()
+
+	answer, err := link.Ask(ctx, server.Bus(), module, tool, arguments, *wait)
+	if err != nil {
+		return err
+	}
+	// The answer as the module gave it, to standard output, for a person or a program. A tool
+	// that answered with an error has still answered: printed the same way, and the exit status
+	// says which.
+	body, err := json.Marshal(answer)
+	if err != nil {
+		return err
+	}
+	fmt.Fprintln(os.Stdout, string(body))
+	if answer.Error != "" {
+		return fmt.Errorf("%s.%s answered with an error: %s", module, tool, answer.Error)
+	}
+	return nil
+}

cmd/mesh-controller/asker.go

@@ -0,0 +1,946 @@
+package main
+
+// The controller asks, and acts on the operator's warrant (novox/hq ADR 0259 §6). It holds no channel, no
+// identity and no factor: it asks the router like any other module, and performs the answer chosen with its
+// own grant.
+//
+//   - **For every open, unsilenced condition that needs the operator and names its answers**, one ask is
+//     published on the `operator-channel` seat under the controller's own name: the condition's words, its
+//     actions as options at their levels (Silence acknowledges; Release, Stop, Start and Restart approve),
+//     answered by the operator, expiring after a day (a week when every option only acknowledges). A
+//     condition that clears, is silenced, or changes its answers has its ask cancelled; an ask that expired
+//     unanswered is asked again while the condition lasts; one the router refused is asked again after a wait
+//     that grows with each refusal in a row, at most half an hour, so a refusal is never believed longer. Each ask is kept in the controller's bucket
+//     `asked`, so a restart neither asks twice nor forgets.
+//   - **On a warrant**, heard on the seat's event under the controller's own name (which only the router may
+//     say), the controller acts once per ask: only for an ask it holds, only for the option it offered at
+//     that option's level, and only while the condition is still open. It performs the action as itself —
+//     a silence through its own conditions, any other through the verb the action names — with the warrant's
+//     words as its why, and records it in the hand-act log as the operator's decision, naming the channel,
+//     the ask and the proofs. An ask that ended without a choice is recorded and nothing is done.
+//   - **A warrant it missed** while away is read from the router's record of its asks, under its own name.
+
+import (
+	"context"
+	"crypto/rand"
+	"encoding/hex"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+
+	"git.novox.be/novox/mesh-sdk/go/asks"
+
+	"github.com/novox/mesh-controller/internal/broker"
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// The asker's name on the seat: the controller's module.
+const askerName = broker.ControllerSeat
+
+// How long an ask lasts: a day when an answer approves, a week when every answer only acknowledges.
+const (
+	// askApproveFor is a day less a margin, so an ask is never refused at the router for lasting a day and
+	// a moment (the SDK's bound is a day).
+	askApproveFor     = 24*time.Hour - 10*time.Minute
+	askAcknowledgeFor = 7 * 24 * time.Hour
+	// askEvery is how often what is open is asked about again, beside every change.
+	askEvery = time.Minute
+	// askCatchUpAfter is how old an open ask is before the router's record of it is read: a warrant heard
+	// on the event needs no reading.
+	askCatchUpAfter = 2 * time.Minute
+	// askAgainAfterAnswer is how long a condition the operator answered is not asked about again with the
+	// same answers: what was chosen takes a while to clear it, and asking again at once would ask twice.
+	askAgainAfterAnswer = time.Hour
+	// askMostOpen is how many asks the controller holds open at once (the router refuses a fourth): the
+	// most urgent conditions first, then the oldest.
+	askMostOpen = asks.MostOpen
+	// askRefusedRetryMost is the longest a refusal is believed without asking again (novox/hq issue 369): the
+	// router refused while its channels had not yet said they could send, the channels could send twenty
+	// minutes later, and the controller repeated that refusal for eleven hours. A refused ask is asked again
+	// after askEvery, then twice as long after each refusal in a row, never longer than this — and at once when
+	// the channels change.
+	askRefusedRetryMost = 30 * time.Minute
+	// askRefusedCounted is how far back refusals in a row are counted for that wait.
+	askRefusedCounted = 6 * time.Hour
+	// askVerdictWait is how long an ask made again after a refusal waits for the router's word before it is
+	// taken as taken: the router refuses an ask as it reads it, so a refusal comes within seconds. Meanwhile
+	// the condition saying it was not delivered stands as it was, neither cleared nor raised again.
+	askVerdictWait = 2 * time.Minute
+)
+
+// refusedRetryAfter is how long a part refused n times in a row waits before it is asked again.
+func refusedRetryAfter(n int) time.Duration {
+	wait := askEvery
+	for i := 1; i < n && wait < askRefusedRetryMost; i++ {
+		wait *= 2
+	}
+	return min(wait, askRefusedRetryMost)
+}
+
+// What became of an ask, as the controller keeps it.
+const (
+	askOpen      = "open"
+	askCancelled = "cancelled"
+)
+
+// asked is one ask the controller made, as it keeps it.
+type asked struct {
+	ID        string `json:"id"`
+	Condition string `json:"condition"`
+	// Channels is what the channels were when it was asked (asker.channels): an ask the router refused is asked
+	// again at once when the condition's answers or the channels change, and otherwise after a wait that grows
+	// with each refusal in a row (refusedRetryAfter, novox/hq issue 369).
+	Channels string              `json:"channels,omitempty"`
+	Ask      asks.Ask            `json:"ask"`
+	Actions  []conditions.Action `json:"actions"`
+	// Options are the actions by option id.
+	Options map[string]int `json:"options"`
+	State   string         `json:"state"`
+	Opened  time.Time      `json:"opened"`
+	Ended   time.Time      `json:"ended,omitempty"`
+	Warrant *asks.Warrant  `json:"warrant,omitempty"`
+	// Acted is what the controller did on the warrant: empty before it did anything, "acting" while it acts,
+	// then "done", "failed: …" or "nothing: …". Anything but empty is never acted on again.
+	Acted string `json:"acted,omitempty"`
+	// Part is which ask of its condition this is (askPart): empty for the one that carries the condition's
+	// answers, or the authorising ones where it has both; "acknowledge" for its acknowledging answers asked
+	// apart (the review of 2026-10-09, M1).
+	Part string `json:"part,omitempty"`
+	// Rehearsal is an ask started at the controller's terminal (rehearse.go): about no condition, its answers
+	// perform nothing, and the reconciling of conditions leaves it alone.
+	Rehearsal bool `json:"rehearsal,omitempty"`
+	// Proposal is a settings layer proposed through a verb (proposals.go, novox/hq ADR 0277): about no
+	// condition, set on Approve by the serving controller itself, and left alone by the reconciling of conditions.
+	Proposal *settingsProposal `json:"proposal,omitempty"`
+}
+
+// ofACondition says an ask is one of a condition's: not a rehearsal, not a proposal.
+func (r asked) ofACondition() bool { return !r.Rehearsal && r.Proposal == nil }
+
+// partKey is an ask's place among what is asked: its condition and its part.
+func partKey(condition, part string) string { return condition + "#" + part }
+
+// partAcknowledge is the part of a condition asked apart for its acknowledging answers.
+const partAcknowledge = "acknowledge"
+
+// askPart is one ask a condition is asked with: its part, what it is about, and its answers.
+type askPart struct {
+	name    string
+	about   string
+	actions []conditions.Action
+}
+
+// levelOf is an action's level as an option offers it: one that says none is never taken for less than
+// approve.
+func levelOf(act conditions.Action) asks.Level {
+	if act.Level == "" {
+		return asks.Approve
+	}
+	return asks.Level(act.Level)
+}
+
+// partsOf is the asks a condition is asked with (the review of 2026-10-09, M1): one, when its answers are all
+// of one kind; else its authorising answers (Release, Stop, Restart) in one ask, about the condition, and its
+// acknowledging ones (Silence) in another. **An acknowledgement never shares an ask with an approval**: a
+// channel that only acknowledges would otherwise answer the ask, and end the approval with it.
+func partsOf(c conditions.Condition) []askPart {
+	var ack, auth []conditions.Action
+	for _, act := range c.Actions {
+		if levelOf(act) == asks.Acknowledge {
+			ack = append(ack, act)
+		} else {
+			auth = append(auth, act)
+		}
+	}
+	if len(ack) == 0 || len(auth) == 0 {
+		return []askPart{{about: c.Key, actions: c.Actions}}
+	}
+	return []askPart{{about: c.Key, actions: auth},
+		{name: partAcknowledge, about: c.Key + "." + partAcknowledge, actions: ack}}
+}
+
+// askedStore keeps the asks (broker.AskedBucket). **Every write after the first is a compare-and-set** (the
+// review of 2026-10-09, L2): an ask is created once, and changed only over the revision it was read at, the
+// change decided again on what is read — so two controllers, or two deliveries of one warrant, never write
+// over each other, and of two that would act only the one whose write stands does.
+type askedStore interface {
+	Get(ctx context.Context, id string) (*asked, error)
+	// Create keeps a new ask, and refuses one already kept under its id.
+	Create(ctx context.Context, a asked) error
+	// Change applies change to the ask kept under id, by compare-and-set, and says whether its write stood.
+	// change says whether to write at all; on a write that came between, it is asked again on what is read.
+	Change(ctx context.Context, id string, change func(*asked) bool) (bool, error)
+	All(ctx context.Context) ([]asked, error)
+}
+
+// askChangeTries is how often a change is read and tried again when another write came between.
+const askChangeTries = 5
+
+// asker is the controller asking the operator and acting on the answer.
+type asker struct {
+	open    func(ctx context.Context) ([]conditions.Condition, error)
+	silence func(ctx context.Context, key string, d time.Duration, by, why string) error
+	store   askedStore
+	// publish puts a message on a subject's stream, de-duplicated by id.
+	publish func(ctx context.Context, subject string, body []byte, id string) error
+	// call performs an action's verb with its arguments, as the controller.
+	call func(ctx context.Context, a conditions.Action, args map[string]string) error
+	// setLayer sets a proposed settings layer on the operator's warrant (novox/hq ADR 0277); nil cannot.
+	setLayer setOnWarrant
+	// record writes the hand-act log.
+	record func(ctx context.Context, act link.HandAct) error
+	// routerRecord reads the router's record of an ask for a warrant missed; nil reads nothing.
+	routerRecord func(ctx context.Context, id string) (*asks.Warrant, error)
+	// routerHere says whether a router holds the seat and takes asks under the asker's name; nil is yes.
+	routerHere func(ctx context.Context) (bool, error)
+	// grantHeld says whether the bus holds the controller's grant to ask: the user list the bus's machine was
+	// last sent is the one the mesh composes now (novox/hq issue 353). The grant is composed from the router's
+	// assignment and reaches the bus only when that machine is next pushed, so between `assign` and `push`
+	// the record says a router is here and the bus refuses every ask. why says what to do; nil is yes.
+	grantHeld func(ctx context.Context) (held bool, why string, err error)
+	// channels is what the channels are now, as a fingerprint: who holds which kind, promising what.
+	channels func(ctx context.Context) string
+	// raise keeps the asker's own condition (sourceAsker): which conditions needing the operator could not be
+	// asked, and why. Nil raises nothing (a test that does not look).
+	raise func(ctx context.Context, obs []conditions.Observation) error
+	now   func() time.Time
+	logf  func(string, ...any)
+
+	saidNoRouter bool
+	saidNoGrant  bool
+	// saidGrantCaveat is whether a grant held with a caveat was said, so it is said once.
+	saidGrantCaveat bool
+
+	mu     sync.Mutex
+	nudged chan struct{}
+}
+
+func (a *asker) nudge() {
+	if a == nil {
+		return
+	}
+	a.mu.Lock()
+	if a.nudged == nil {
+		a.nudged = make(chan struct{}, 1)
+	}
+	ch := a.nudged
+	a.mu.Unlock()
+	select {
+	case ch <- struct{}{}:
+	default:
+	}
+}
+
+// keep asks until ctx ends: now, on every change of a condition, and every askEvery.
+func (a *asker) keep(ctx context.Context) {
+	a.nudge()
+	tick := time.NewTicker(askEvery)
+	defer tick.Stop()
+	a.mu.Lock()
+	nudged := a.nudged
+	a.mu.Unlock()
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-tick.C:
+		case <-nudged:
+		}
+		if err := a.reconcile(ctx); err != nil {
+			a.logf("what the operator is asked could not be brought up to date: %v", err)
+		}
+	}
+}
+
+// wants says whether a condition is one to ask about now.
+func wants(c conditions.Condition, now time.Time) bool {
+	return len(c.Actions) > 0 && c.Needs != "" && !c.SilencedAt(now)
+}
+
+func sameAsked(a []conditions.Action, b []conditions.Action) bool {
+	x, _ := json.Marshal(a)
+	y, _ := json.Marshal(b)
+	return string(x) == string(y)
+}
+
+// reconcile brings what is asked in line with what is open.
+func (a *asker) reconcile(ctx context.Context) error {
+	now := a.now()
+	if a.routerHere != nil {
+		here, err := a.routerHere(ctx)
+		if err != nil {
+			return err
+		}
+		if !here {
+			if !a.saidNoRouter {
+				a.logf("no router takes asks under the controller's name (a module declaring %s with its ask "+
+					"named by its caller, assigned): the operator is asked nothing until one is", broker.AsksSeat)
+				a.saidNoRouter = true
+			}
+			open, err := a.open(ctx)
+			if err != nil {
+				return err
+			}
+			var unasked []conditions.Condition
+			for _, c := range open {
+				if wants(c, now) {
+					unasked = append(unasked, c)
+				}
+			}
+			return a.sayUnasked(ctx, unasked, "no router takes the controller's asks: no module holding "+
+				broker.AsksSeat+" that takes an ask under its asker's name is assigned")
+		}
+		a.saidNoRouter = false
+	}
+	if a.grantHeld != nil {
+		held, why, err := a.grantHeld(ctx)
+		if err != nil {
+			return err
+		}
+		if !held {
+			if !a.saidNoGrant {
+				a.logf("the bus does not hold the controller's grant to ask yet: %s; the operator is asked nothing until it does", why)
+				a.saidNoGrant = true
+			}
+			open, err := a.open(ctx)
+			if err != nil {
+				return err
+			}
+			var unasked []conditions.Condition
+			for _, c := range open {
+				if wants(c, now) {
+					unasked = append(unasked, c)
+				}
+			}
+			return a.sayUnasked(ctx, unasked, "the bus does not hold the controller's grant to ask yet: "+why)
+		}
+		if why != "" && !a.saidGrantCaveat {
+			// Held, with a caveat worth one line (an older bus module cannot confirm the reload).
+			a.logf("the controller asks: %s", why)
+			a.saidGrantCaveat = true
+		} else if why == "" {
+			a.saidGrantCaveat = false
+		}
+		a.saidNoGrant = false
+	}
+	channels := ""
+	if a.channels != nil {
+		channels = a.channels(ctx)
+	}
+	open, err := a.open(ctx)
+	if err != nil {
+		return err
+	}
+	all, err := a.store.All(ctx)
+	if err != nil {
+		return err
+	}
+	byCondition := map[string]asked{} // by partKey
+	// What is open and not a condition's — a rehearsal, a proposal — still counts toward what the router holds
+	// open for the controller (askMostOpen); expired unanswered, it is kept so, as the router says it too.
+	otherOpen := 0
+	for _, r := range all {
+		if r.State == askOpen && !r.ofACondition() && !now.Before(r.Ask.Expires) {
+			if _, err := a.store.Change(ctx, r.ID, func(x *asked) bool {
+				if x.State != askOpen || x.Acted != "" {
+					return false
+				}
+				x.State, x.Ended, x.Acted = string(asks.OutcomeExpired), now, "nothing: the ask expired unanswered"
+				return true
+			}); err != nil {
+				return err
+			}
+			continue
+		}
+		if r.State == askOpen && !r.ofACondition() {
+			otherOpen++
+		}
+		if r.State == askOpen && r.ofACondition() {
+			k := partKey(r.Condition, r.Part)
+			if prior, held := byCondition[k]; !held || r.Opened.After(prior.Opened) {
+				byCondition[k] = r
+			}
+		}
+	}
+	// A warrant missed while away, read from the router's record: for a condition's ask, and for a proposal's or a
+	// rehearsal's alike.
+	if a.routerRecord != nil {
+		var lookedUp []asked
+		for _, r := range byCondition {
+			lookedUp = append(lookedUp, r)
+		}
+		for _, r := range all {
+			if r.State == askOpen && !r.ofACondition() {
+				lookedUp = append(lookedUp, r)
+			}
+		}
+		for _, r := range lookedUp {
+			if now.Sub(r.Opened) < askCatchUpAfter {
+				continue
+			}
+			if w, err := a.routerRecord(ctx, r.ID); err == nil && w != nil {
+				body, _ := json.Marshal(w)
+				if err := a.Decided(ctx, body); err != nil {
+					return err
+				}
+			}
+		}
+		if all, err = a.store.All(ctx); err != nil {
+			return err
+		}
+		byCondition = map[string]asked{}
+		for _, r := range all {
+			if r.State == askOpen && r.ofACondition() {
+				byCondition[partKey(r.Condition, r.Part)] = r
+			}
+		}
+	}
+	// What the operator answered lately, by condition: not asked again at once; and what the router refused,
+	// newest first: not asked again until the answers or the channels change.
+	answered, refused := map[string]asked{}, map[string]asked{}
+	for _, r := range all {
+		k := partKey(r.Condition, r.Part)
+		if r.State == string(asks.OutcomeChosen) && now.Sub(r.Ended) < askAgainAfterAnswer {
+			answered[k] = r
+		}
+		if r.State == string(asks.OutcomeRefused) {
+			if prior, has := refused[k]; !has || r.Opened.After(prior.Opened) {
+				refused[k] = r
+			}
+		}
+	}
+	// Refusals in a row, by part: those since the last ask that was not refused, within askRefusedCounted.
+	// superseded: a part asked since its last refusal, by an ask the router did not refuse — open, answered,
+	// expired or cancelled. Its refusal is history then, never said again (the review of PR 198: an answered
+	// retry brought the refusal back).
+	inRow, superseded := map[string]int{}, map[string]asked{}
+	for k, last := range refused {
+		for _, r := range all {
+			if partKey(r.Condition, r.Part) == k && r.State != string(asks.OutcomeRefused) && r.State != askUnsent &&
+				r.Opened.After(last.Opened) && r.Opened.After(superseded[k].Opened) {
+				superseded[k] = r
+			}
+		}
+		var since time.Time
+		for _, r := range all {
+			if partKey(r.Condition, r.Part) == k && r.State != string(asks.OutcomeRefused) && r.State != askUnsent &&
+				!r.Opened.After(last.Opened) && r.Opened.After(since) {
+				since = r.Opened
+			}
+		}
+		for _, r := range all {
+			if partKey(r.Condition, r.Part) == k && r.State == string(asks.OutcomeRefused) && r.Opened.After(since) &&
+				now.Sub(r.Opened) < askRefusedCounted {
+				inRow[k]++
+			}
+		}
+	}
+	wanted := map[string]bool{}
+	var unasked []conditions.Condition // refused by the router, and nothing it was refused for changed
+	var refusedWords []string
+	// The most urgent first, then the oldest: those are asked when no more than askMostOpen may be.
+	sort.SliceStable(open, func(i, j int) bool {
+		ui, uj := open[i].Severity == conditions.Urgent, open[j].Severity == conditions.Urgent
+		if ui != uj {
+			return ui
+		}
+		if !open[i].Raised.Equal(open[j].Raised) {
+			return open[i].Raised.Before(open[j].Raised)
+		}
+		return open[i].Key < open[j].Key
+	})
+	openNow := otherOpen
+	for _, c := range open {
+		if !wants(c, now) {
+			continue
+		}
+		for _, p := range partsOf(c) {
+			if r, held := byCondition[partKey(c.Key, p.name)]; held && sameAsked(r.Actions, p.actions) && now.Before(r.Ask.Expires) {
+				openNow++
+			}
+		}
+	}
+	for _, c := range open {
+		if !wants(c, now) {
+			continue
+		}
+		saidUnasked := false
+		for _, p := range partsOf(c) {
+			key := partKey(c.Key, p.name)
+			wanted[key] = true
+			if r, was := refused[key]; was && sameAsked(r.Actions, p.actions) {
+				cur, held := byCondition[key]
+				ended := r.Ended
+				if ended.IsZero() {
+					ended = r.Opened
+				}
+				later, asked := superseded[key]
+				waiting := !held && !asked && r.Channels == channels && now.Sub(ended) < refusedRetryAfter(inRow[key])
+				// Asked again now (the wait over), or lately and the router's word not in yet: said as it was until
+				// that word, so the condition neither clears nor is raised again at each try.
+				retrying := !held && !asked && !waiting
+				verdictDue := held && asked && later.ID == cur.ID && now.Sub(cur.Opened) < askVerdictWait
+				if waiting || retrying || verdictDue {
+					if !saidUnasked {
+						unasked, saidUnasked = append(unasked, c), true
+					}
+					if r.Warrant != nil && r.Warrant.Words != "" {
+						refusedWords = append(refusedWords, r.Warrant.Words)
+					}
+				}
+				if waiting {
+					continue // refused lately, and nothing it was refused for has changed: asked again after the wait
+				}
+			}
+			if r, done := answered[key]; done && sameAsked(r.Actions, p.actions) {
+				if _, held := byCondition[key]; !held {
+					continue
+				}
+			}
+			if r, held := byCondition[key]; held {
+				switch {
+				case !sameAsked(r.Actions, p.actions):
+					if err := a.cancel(ctx, r, "its answers changed"); err != nil {
+						return err
+					}
+				case !now.Before(r.Ask.Expires):
+					// Expired unanswered: the router says so too; asked again below while it lasts.
+					if _, err := a.store.Change(ctx, r.ID, func(x *asked) bool {
+						if x.State != askOpen {
+							return false
+						}
+						x.State, x.Ended = string(asks.OutcomeExpired), now
+						return true
+					}); err != nil {
+						return err
+					}
+					openNow--
+				default:
+					continue
+				}
+			}
+			if openNow >= askMostOpen {
+				continue // asked when one of the open ones ends, most urgent first
+			}
+			if err := a.ask(ctx, c, p, channels); err != nil {
+				a.logf("the operator could not be asked about %s: %v", c.Key, err)
+				continue
+			}
+			openNow++
+		}
+	}
+	stillOpen := map[string]conditions.Condition{}
+	for _, c := range open {
+		stillOpen[c.Key] = c
+	}
+	for key, r := range byCondition {
+		if wanted[key] {
+			continue
+		}
+		// **A silence never takes an approval back** (the confirmation review of 2026-10-09, M1). Silence is an
+		// acknowledgement — anyone at the desk may give it — so a condition silenced while its approval is asked
+		// keeps that ask open, unchanged, until it is answered on a channel that proves who answered, or expires.
+		// It is not asked again once it ends, while the silence lasts.
+		if c, open := stillOpen[r.Condition]; open && c.SilencedAt(now) && r.Ask.Highest() != asks.Acknowledge &&
+			now.Before(r.Ask.Expires) && keepsItsAnswers(c, r) {
+			continue
+		}
+		if err := a.cancel(ctx, r, "the condition ended, was silenced or needs nothing now"); err != nil {
+			return err
+		}
+	}
+	why := "the router refused the ask"
+	if len(refusedWords) > 0 {
+		why += ": " + refusedWords[0]
+	}
+	return a.sayUnasked(ctx, unasked, why)
+}
+
+// keepsItsAnswers says a condition still offers the answers an ask kept was asked with.
+func keepsItsAnswers(c conditions.Condition, r asked) bool {
+	for _, p := range partsOf(c) {
+		if partKey(c.Key, p.name) == partKey(r.Condition, r.Part) {
+			return sameAsked(r.Actions, p.actions)
+		}
+	}
+	return false
+}
+
+// sourceAsker raises the asker's own condition.
+const sourceAsker = "asker"
+
+// sayUnasked keeps the asker's one condition: while a condition that needs the operator could not be asked
+// on any channel, said loudly (failure must be loud), cleared when every one could be.
+func (a *asker) sayUnasked(ctx context.Context, unasked []conditions.Condition, why string) error {
+	if a.raise == nil {
+		return nil
+	}
+	var obs []conditions.Observation
+	if len(unasked) > 0 {
+		keys := make([]string, 0, len(unasked))
+		severity := conditions.Warning
+		for _, c := range unasked {
+			keys = append(keys, c.Key)
+			if c.Severity == conditions.Urgent {
+				severity = conditions.Urgent
+			}
+		}
+		sort.Strings(keys)
+		obs = append(obs, conditions.Observation{Scope: conditions.ScopeSeat, ID: broker.AsksSeat, Token: "unasked",
+			Kind: "asks-undelivered", Severity: severity, Source: sourceAsker,
+			Summary: fmt.Sprintf("%d condition(s) that need the operator could not be asked on any channel: %s; %s",
+				len(keys), strings.Join(keys, ", "), why),
+			Headline:    "Questions for you not delivered",
+			Explanation: "The mesh could not send you its questions on any channel.",
+			Needs:       "answer them from the mesh MCP server, and check why no channel carries them.",
+			Resolved:    "The mesh can ask you again"})
+	}
+	if err := a.raise(ctx, obs); err != nil {
+		a.logf("whether the operator could be asked could not be kept as a condition: %v", err)
+	}
+	return nil
+}
+
+// optionID is an action's label as an option's id: "Silence for a week" is silence-for-a-week.
+func optionID(label string) string {
+	var b strings.Builder
+	dash := false
+	for _, r := range strings.ToLower(label) {
+		switch {
+		case r >= 'a' && r <= 'z', r >= '0' && r <= '9':
+			b.WriteRune(r)
+			dash = false
+		case !dash && b.Len() > 0:
+			b.WriteByte('-')
+			dash = true
+		}
+	}
+	return strings.TrimSuffix(b.String(), "-")
+}
+
+// doesWords is what an action does, in the words an option says it with.
+func doesWords(act conditions.Action) string {
+	switch {
+	case act.Arguments["silence"] != "":
+		return "nothing more is said of it for a week"
+	case act.Verb == "mesh-delivery.release":
+		return "the delivery goes on"
+	case act.Verb == "mesh-delivery.stop":
+		return "the delivery ends"
+	case act.Verb == broker.ControllerSeat+".plans" && act.Arguments["go"] != "":
+		return "the delivery starts"
+	case act.Verb == broker.ControllerSeat+".plans" && act.Arguments["stop"] != "":
+		return "the delivery is stopped"
+	case strings.HasSuffix(act.Verb, ".restart"):
+		return "its service is restarted on " + act.Machine
+	}
+	return strings.ToLower(act.Label)
+}
+
+// askText is a condition's words as an ask says them: without where an answer is given when no channel can
+// give it (FromMeshMCPServer), since the ask is answered on a channel and the router says where else.
+func askText(s string) string {
+	for _, with := range []string{", " + FromMeshMCPServer, " " + FromMeshMCPServer} {
+		s = strings.ReplaceAll(s, with, ".")
+	}
+	return strings.ReplaceAll(s, "..", ".")
+}
+
+// askOf is the ask one part of a condition is asked with.
+func askOf(id string, c conditions.Condition, p askPart, now time.Time) (asks.Ask, map[string]int) {
+	q := asks.Ask{ID: id, Headline: c.Headline, Explanation: askText(c.Explanation), Who: asks.Operator,
+		OnExpiry: "nothing is done, and you are asked again while it lasts", About: p.about,
+		Urgent: c.Severity == conditions.Urgent}
+	options := map[string]int{}
+	approves := false
+	for i, act := range p.actions {
+		level := levelOf(act) // an action that says nothing of its level is never taken for less than approve
+		approves = approves || level != asks.Acknowledge
+		oid := optionID(act.Label)
+		options[oid] = i
+		// Every option binds the exact act it stands for (novox/hq ADR 0259 §6): the verb, the machine and
+		// every argument. The warrant then authorises that act and no other.
+		binds, _ := asks.ActDigest(boundAct(act))
+		q.Options = append(q.Options, asks.Option{ID: oid, Label: act.Label, Does: doesWords(act), Level: level,
+			Binds: binds})
+	}
+	q.Expires = now.Add(askAcknowledgeFor)
+	if approves {
+		q.Expires = now.Add(askApproveFor)
+	}
+	return q, options
+}
+
+// boundAct is what an option's Binds digests: the act exactly as the controller will perform it — its verb,
+// machine, level, and each argument as "arg.<name>" — and never its label or words.
+func boundAct(act conditions.Action) asks.Act {
+	out := asks.Act{"verb": act.Verb, "machine": act.Machine, "level": act.Level}
+	for k, v := range act.Arguments {
+		out["arg."+k] = v
+	}
+	return out
+}
+
+func newAskID() string {
+	var b [8]byte
+	_, _ = rand.Read(b[:])
+	return "c" + hex.EncodeToString(b[:])
+}
+
+// askUnsent is an ask kept and never published: asked again at the next look.
+const askUnsent = "unsent"
+
+// ask publishes one ask about a part of a condition, kept before it is published (the review of 2026-10-09,
+// L3): a warrant for it then always finds it, and one whose publishing failed is marked so and asked again.
+func (a *asker) ask(ctx context.Context, c conditions.Condition, p askPart, channels string) error {
+	now := a.now()
+	id := newAskID()
+	q, options := askOf(id, c, p, now)
+	if err := q.Check(now); err != nil {
+		return err
+	}
+	body, err := json.Marshal(q)
+	if err != nil {
+		return err
+	}
+	if err := a.store.Create(ctx, asked{ID: id, Condition: c.Key, Part: p.name, Ask: q, Actions: p.actions,
+		Options: options, State: askOpen, Opened: now, Channels: channels}); err != nil {
+		return fmt.Errorf("the ask could not be kept, so it was not asked: %w", err)
+	}
+	if err := a.publish(ctx, asks.AskSubject(askerName), body, "ask."+id); err != nil {
+		if _, cerr := a.store.Change(ctx, id, func(x *asked) bool {
+			if x.State != askOpen || x.Acted != "" {
+				return false
+			}
+			x.State, x.Ended, x.Acted = askUnsent, a.now(), "nothing: it could not be published: "+err.Error()
+			return true
+		}); cerr != nil {
+			a.logf("the ask %s could not be published, and could not be marked so: %v", id, cerr)
+		}
+		return err
+	}
+	a.logf("asked the operator about %s (%s): %d answer(s)", c.Key, id, len(q.Options))
+	return nil
+}
+
+// cancel takes an ask back: kept cancelled first, so a warrant that comes after is refused, then said to the
+// router; a cancel the router did not hear leaves the ask to expire there, and nothing is done on it here.
+func (a *asker) cancel(ctx context.Context, r asked, why string) error {
+	stood, err := a.store.Change(ctx, r.ID, func(x *asked) bool {
+		if x.State != askOpen {
+			return false
+		}
+		x.State, x.Ended = askCancelled, a.now()
+		return true
+	})
+	if err != nil || !stood {
+		return err
+	}
+	body, _ := json.Marshal(map[string]string{"id": r.ID})
+	if err := a.publish(ctx, asks.CancelSubject(askerName), body, "cancel."+r.ID); err != nil {
+		a.logf("the ask %s about %s is taken back here, and the router could not be told (%v): it expires there, "+
+			"and no answer to it is acted on", r.ID, r.Condition, err)
+		return nil
+	}
+	a.logf("took back the ask %s about %s: %s", r.ID, r.Condition, why)
+	return nil
+}
+
+// Decided takes the router's word on one of the controller's asks (link.Decider). An error is returned only
+// when what was decided could not be kept, so the word is held and heard again.
+func (a *asker) Decided(ctx context.Context, body []byte) error {
+	var w asks.Warrant
+	if err := json.Unmarshal(body, &w); err != nil {
+		a.logf("the router's word on an ask could not be read; ignored: %v", err)
+		return nil
+	}
+	if w.Asker != askerName {
+		a.logf("REFUSED a warrant for %s's ask %s: the controller acts only on its own", w.Asker, w.Ask)
+		return nil
+	}
+	r, err := a.store.Get(ctx, w.Ask)
+	if err != nil {
+		return err
+	}
+	if r == nil {
+		a.logf("REFUSED a warrant for the ask %s, which the controller does not hold", w.Ask)
+		return nil
+	}
+	if r.Acted != "" {
+		return nil // heard again: acted on once
+	}
+	now := a.now()
+	if w.Outcome != asks.OutcomeChosen {
+		acted := "nothing: the ask " + string(w.Outcome)
+		if w.Words != "" {
+			acted += ": " + w.Words
+		}
+		if _, err := a.store.Change(ctx, r.ID, func(x *asked) bool {
+			if x.Acted != "" {
+				return false
+			}
+			x.State, x.Ended, x.Warrant, x.Acted = string(w.Outcome), now, &w, acted
+			return true
+		}); err != nil {
+			return err
+		}
+		a.logf("the ask %s about %s ended %s; nothing is done", r.ID, r.Condition, w.Outcome)
+		return nil
+	}
+	if r.State != askOpen {
+		// Cancelled, replaced or expired in the controller's own record: no answer to it is acted on.
+		a.logf("REFUSED a warrant for the ask %s, which is %s in the controller's own record", r.ID, r.State)
+		return nil
+	}
+	option, err := w.For(askerName, r.Ask)
+	if err != nil {
+		a.logf("REFUSED a warrant for the ask %s: %v", r.ID, err)
+		return nil
+	}
+	index, offered := r.Options[option.ID]
+	if !offered || index >= len(r.Actions) {
+		a.logf("REFUSED a warrant for the ask %s: it chose %s, which no action stands for", r.ID, option.ID)
+		return nil
+	}
+	act := r.Actions[index]
+	// The act about to be performed is the one the option bound when the controller asked: a record changed
+	// since is refused, never performed.
+	if err := option.Performs(boundAct(act)); err != nil {
+		a.logf("REFUSED a warrant for the ask %s: %v", r.ID, err)
+		return nil
+	}
+	open, err := a.open(ctx)
+	if err != nil {
+		return err
+	}
+	stillOpen := r.Rehearsal || r.Proposal != nil // a rehearsal and a proposal are about no condition
+	for _, c := range open {
+		stillOpen = stillOpen || c.Key == r.Condition
+	}
+	if !stillOpen {
+		// The asker checks the state is still what it asked about before it acts (to-be 46 §10, step 7).
+		if _, err := a.store.Change(ctx, r.ID, func(x *asked) bool {
+			if x.State != askOpen || x.Acted != "" {
+				return false
+			}
+			x.State, x.Warrant, x.Ended, x.Acted = string(asks.OutcomeChosen), &w, now,
+				"nothing: the condition ended before the answer"
+			return true
+		}); err != nil {
+			return err
+		}
+		a.logf("%s, for %s, which ended meanwhile: nothing is done", w.Says(), r.Condition)
+		return nil
+	}
+	// Claimed before acting, by compare-and-set: only the delivery whose write stands acts (security review
+	// of 2026-10-08, finding 9). Not by the warrant's message id, which another publisher could take first:
+	// the controller's own record decides.
+	claimed, err := a.store.Change(ctx, r.ID, func(x *asked) bool {
+		if x.State != askOpen || x.Acted != "" {
+			return false
+		}
+		x.State, x.Warrant, x.Acted = string(asks.OutcomeChosen), &w, "acting"
+		return true
+	})
+	if err != nil {
+		return err
+	}
+	if !claimed {
+		a.logf("the warrant for the ask %s was already taken by another delivery; nothing more is done", r.ID)
+		return nil
+	}
+	r.Acted = "acting"
+
+	why := fmt.Sprintf("%s (ask %s)", w.Says(), r.ID)
+	args := map[string]string{}
+	for k, v := range act.Arguments {
+		args[k] = v
+	}
+	if v, takes := args["why"]; takes && v == "" {
+		args["why"] = why
+	}
+	var acted error
+	outcome := "done"
+	switch {
+	case r.Rehearsal && act.Verb == rehearsalVerb:
+		// A rehearsal's answer performs nothing: it is recorded below as the operator's decision.
+	case r.Proposal != nil && act.Verb == proposalVerb:
+		// A proposed settings layer, set by this controller itself on Approve (novox/hq ADR 0277): the act's
+		// digest of the values is held to the record's own values before anything is set.
+		outcome, acted = a.decideProposal(ctx, *r, act, w)
+		if acted == nil && outcome != "" && !strings.HasPrefix(outcome, "nothing") {
+			outcome = "done: " + outcome
+		}
+	case act.Arguments["silence"] != "":
+		acted = a.silence(ctx, act.Arguments["silence"], conditions.MaxSilence, byWords(w), why)
+	default:
+		acted = a.call(ctx, act, args)
+	}
+	ended := a.now()
+	if acted != nil {
+		outcome = "failed: " + acted.Error()
+	}
+	r.Ended, r.Acted = ended, outcome
+	if _, err := a.store.Change(ctx, r.ID, func(x *asked) bool {
+		if x.Acted != "acting" {
+			return false
+		}
+		x.Ended, x.Acted = ended, outcome
+		return true
+	}); err != nil {
+		a.logf("%s was acted on (%s), and how it ended could NOT be kept: %v", r.ID, outcome, err)
+	}
+	verbArgs := []string{act.Verb}
+	if act.Machine != "" {
+		verbArgs = append(verbArgs, "on "+act.Machine)
+	}
+	keys := make([]string, 0, len(args))
+	for k := range args {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	for _, k := range keys {
+		if k != "why" {
+			verbArgs = append(verbArgs, k+"="+args[k])
+		}
+	}
+	if err := a.record(ctx, link.HandAct{Verb: handActWarrant, Args: verbArgs, Why: why, By: byWords(w),
+		Cause: conditions.CauseOperatorAnswer, Condition: r.Condition, Via: viaWords(w), Ask: r.ID,
+		Proofs: w.Proofs, RequestedBy: r.Condition, Outcome: r.Acted}); err != nil {
+		a.logf("%s was done, and could NOT be recorded in the hand-act log: %v", why, err)
+	}
+	a.logf("%s: %s", why, r.Acted)
+	return nil
+}
+
+// handActWarrant is the verb an act the operator chose on a warrant is recorded under: a person's decision,
+// never a repair (handActVerbs).
+const handActWarrant = "warrant"
+
+// byWords is who chose, as the hand-act log says it: "the operator, as telegram identity 42".
+func byWords(w asks.Warrant) string {
+	if w.By == nil {
+		return "the operator"
+	}
+	return fmt.Sprintf("the %s, as %s identity %s", w.By.Who, w.By.Kind, w.By.Identity)
+}
+
+// viaWords is the channel an answer came through: its module and kind, and how the sender was known.
+func viaWords(w asks.Warrant) string {
+	if w.By == nil {
+		return w.Channel
+	}
+	via := w.Channel + " (" + w.By.Kind + ")"
+	if w.By.Verified != "" {
+		via += ", " + w.By.Verified
+	}
+	return via
+}
+
+// errNotGranted is an action whose verb the controller's grant does not name.
+var errNotGranted = errors.New("the controller's grant does not name this verb")

cmd/mesh-controller/asker_bus_test.go

@@ -0,0 +1,153 @@
+//go:build integration
+
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/nats-io/nats.go"
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/asks"
+
+	"github.com/novox/mesh-controller/internal/broker"
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/link"
+	"github.com/novox/mesh-controller/internal/testbus"
+)
+
+// busAsker is an asker on a real bus's `asked` bucket, counting what it performs: two of them are two
+// controllers sharing one record.
+type busAskerRig struct {
+	mu     sync.Mutex
+	called int
+	acts   int
+	open   []conditions.Condition
+	sent   [][]byte
+}
+
+func (rig *busAskerRig) asker(t *testing.T, conn *nats.Conn, now time.Time) *asker {
+	return &asker{
+		open: func(context.Context) ([]conditions.Condition, error) {
+			rig.mu.Lock()
+			defer rig.mu.Unlock()
+			return rig.open, nil
+		},
+		silence: func(context.Context, string, time.Duration, string, string) error { return nil },
+		store:   busAsked{conn: conn},
+		publish: func(_ context.Context, subject string, body []byte, _ string) error {
+			rig.mu.Lock()
+			defer rig.mu.Unlock()
+			if subject == asks.AskSubject(askerName) {
+				rig.sent = append(rig.sent, body)
+			}
+			return nil
+		},
+		call: func(context.Context, conditions.Action, map[string]string) error {
+			time.Sleep(20 * time.Millisecond) // long enough for the other delivery to arrive meanwhile
+			rig.mu.Lock()
+			defer rig.mu.Unlock()
+			rig.called++
+			return nil
+		},
+		record: func(context.Context, link.HandAct) error {
+			rig.mu.Lock()
+			defer rig.mu.Unlock()
+			rig.acts++
+			return nil
+		},
+		now:  func() time.Time { return now },
+		logf: t.Logf,
+	}
+}
+
+func askedBus(t *testing.T) *nats.Conn {
+	t.Helper()
+	conn, err := nats.Connect(testbus.URL(t))
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(conn.Close)
+	js, err := jetstream.New(conn)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := js.CreateKeyValue(context.Background(), jetstream.KeyValueConfig{Bucket: broker.AskedBucket}); err != nil {
+		t.Fatal(err)
+	}
+	return conn
+}
+
+// The review of 2026-10-09 (L7): two deliveries of one warrant, to two controllers at once, perform its act
+// exactly once and record it once — the record's compare-and-set decides, never the warrant's message id.
+func TestTwoAnswersAtOnceActOnce(t *testing.T) {
+	conn := askedBus(t)
+	now := time.Date(2026, 10, 9, 14, 0, 0, 0, time.UTC)
+	rig := &busAskerRig{open: []conditions.Condition{heldCondition()}}
+	first, second := rig.asker(t, conn, now), rig.asker(t, conn, now)
+	if err := first.reconcile(context.Background()); err != nil {
+		t.Fatal(err)
+	}
+	if len(rig.sent) != 1 {
+		t.Fatalf("asked %d times", len(rig.sent))
+	}
+	var q asks.Ask
+	_ = json.Unmarshal(rig.sent[0], &q)
+	release, _ := q.Option("release")
+	w := asks.Warrant{Ask: q.ID, Asker: askerName, About: q.About, Outcome: asks.OutcomeChosen, Option: release.ID,
+		Label: release.Label, Level: release.Level, Channel: "telegram", Proofs: []string{"P1"}, At: now,
+		AskDigest: q.Digest(), By: &asks.Person{Who: asks.Operator, Kind: "telegram", Identity: "42", Verified: "user id verified"}}
+	body, _ := json.Marshal(w)
+	var wg sync.WaitGroup
+	for _, a := range []*asker{first, second, first, second} {
+		wg.Add(1)
+		go func(a *asker) {
+			defer wg.Done()
+			if err := a.Decided(context.Background(), body); err != nil {
+				t.Error(err)
+			}
+		}(a)
+	}
+	wg.Wait()
+	if rig.called != 1 || rig.acts != 1 {
+		t.Fatalf("performed %d time(s), recorded %d time(s)", rig.called, rig.acts)
+	}
+	got, err := busAsked{conn: conn}.Get(context.Background(), q.ID)
+	if err != nil || got == nil || got.Acted != "done" {
+		t.Fatalf("kept as %+v (%v)", got, err)
+	}
+}
+
+// The review of 2026-10-09 (L2): a write decided on a record read earlier never lands over one made since. A
+// cancel read before the answer was acted on leaves the act's record as it is.
+func TestAStaleCancelDoesNotWriteOverAnAct(t *testing.T) {
+	conn := askedBus(t)
+	now := time.Date(2026, 10, 9, 14, 0, 0, 0, time.UTC)
+	rig := &busAskerRig{open: []conditions.Condition{heldCondition()}}
+	a := rig.asker(t, conn, now)
+	if err := a.reconcile(context.Background()); err != nil {
+		t.Fatal(err)
+	}
+	var q asks.Ask
+	_ = json.Unmarshal(rig.sent[0], &q)
+	stale, _ := busAsked{conn: conn}.Get(context.Background(), q.ID)
+	release, _ := q.Option("release")
+	w := asks.Warrant{Ask: q.ID, Asker: askerName, About: q.About, Outcome: asks.OutcomeChosen, Option: release.ID,
+		Label: release.Label, Level: release.Level, Channel: "telegram", At: now, AskDigest: q.Digest(),
+		By: &asks.Person{Who: asks.Operator, Kind: "telegram", Identity: "42", Verified: "user id verified"}}
+	body, _ := json.Marshal(w)
+	if err := a.Decided(context.Background(), body); err != nil {
+		t.Fatal(err)
+	}
+	if err := a.cancel(context.Background(), *stale, "the condition ended"); err != nil {
+		t.Fatal(err)
+	}
+	got, _ := busAsked{conn: conn}.Get(context.Background(), q.ID)
+	if got.State != string(asks.OutcomeChosen) || got.Acted != "done" {
+		t.Errorf("a stale cancel wrote over the act: %+v", got)
+	}
+}

cmd/mesh-controller/asker_wire.go

@@ -0,0 +1,589 @@
+package main
+
+// The asker on the bus: its asks in the controller's bucket `asked`, its asks and cancels published on the
+// seat under the controller's name, the verbs a warrant chooses called with the controller's grant, and the
+// router's record of its asks read under its name (novox/hq ADR 0259).
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/nats-io/nats.go"
+	"github.com/nats-io/nats.go/jetstream"
+
+	"git.novox.be/novox/mesh-sdk/go/asks"
+
+	"github.com/novox/mesh-controller/internal/broker"
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// askerFrom is the serving controller's asker; nil in any other process.
+var askerFrom *asker
+
+// askWithin is how long a verb a warrant chose is given to answer.
+const askWithin = time.Minute
+
+type busAsked struct{ conn *nats.Conn }
+
+func (b busAsked) kv(ctx context.Context) (jetstream.KeyValue, error) {
+	js, err := jetstream.New(b.conn)
+	if err != nil {
+		return nil, err
+	}
+	return js.KeyValue(ctx, broker.AskedBucket)
+}
+
+func (b busAsked) Get(ctx context.Context, id string) (*asked, error) {
+	kv, err := b.kv(ctx)
+	if err != nil {
+		return nil, err
+	}
+	e, err := kv.Get(ctx, id)
+	if errors.Is(err, jetstream.ErrKeyNotFound) {
+		return nil, nil
+	}
+	if err != nil {
+		return nil, err
+	}
+	var r asked
+	return &r, json.Unmarshal(e.Value(), &r)
+}
+
+// Create keeps a new ask under its id, and only where none is kept: never over another.
+func (b busAsked) Create(ctx context.Context, r asked) error {
+	kv, err := b.kv(ctx)
+	if err != nil {
+		return err
+	}
+	body, err := json.Marshal(r)
+	if err != nil {
+		return err
+	}
+	_, err = kv.Create(ctx, r.ID, body)
+	return err
+}
+
+// Change applies change to the ask kept under id by compare-and-set on its key's revision (the review of
+// 2026-10-09, L2): read, changed, and written only over the revision read; when another write came between,
+// read again and asked again, at most askChangeTries times. change says whether to write at all.
+func (b busAsked) Change(ctx context.Context, id string, change func(*asked) bool) (bool, error) {
+	kv, err := b.kv(ctx)
+	if err != nil {
+		return false, err
+	}
+	for try := 0; try < askChangeTries; try++ {
+		e, err := kv.Get(ctx, id)
+		if errors.Is(err, jetstream.ErrKeyNotFound) {
+			return false, nil
+		}
+		if err != nil {
+			return false, err
+		}
+		var r asked
+		if err := json.Unmarshal(e.Value(), &r); err != nil {
+			return false, err
+		}
+		if !change(&r) {
+			return false, nil
+		}
+		body, err := json.Marshal(r)
+		if err != nil {
+			return false, err
+		}
+		if _, err := kv.Update(ctx, id, body, e.Revision()); err != nil {
+			var api *jetstream.APIError
+			if errors.Is(err, jetstream.ErrKeyExists) || (errors.As(err, &api) && api.ErrorCode == jetstream.JSErrCodeStreamWrongLastSequence) {
+				continue
+			}
+			return false, err
+		}
+		return true, nil
+	}
+	return false, fmt.Errorf("the ask %s changed under every one of %d tries", id, askChangeTries)
+}
+
+func (b busAsked) All(ctx context.Context) ([]asked, error) {
+	kv, err := b.kv(ctx)
+	if err != nil {
+		return nil, err
+	}
+	lister, err := kv.ListKeys(ctx)
+	if err != nil {
+		return nil, err
+	}
+	defer func() { _ = lister.Stop() }()
+	var out []asked
+	for k := range lister.Keys() {
+		e, err := kv.Get(ctx, k)
+		if err != nil {
+			continue
+		}
+		var r asked
+		if json.Unmarshal(e.Value(), &r) == nil {
+			out = append(out, r)
+		}
+	}
+	return out, nil
+}
+
+// callAction performs an action's verb as the controller, through the grant that names it.
+func callAction(conn *nats.Conn) func(ctx context.Context, a conditions.Action, args map[string]string) error {
+	return func(ctx context.Context, a conditions.Action, args map[string]string) error {
+		seat, verb, ok := strings.Cut(a.Verb, ".")
+		if !ok {
+			return fmt.Errorf("%q names no seat and verb", a.Verb)
+		}
+		body := map[string]any{}
+		for k, v := range args {
+			body[k] = v
+		}
+		if seat == catalogue.DeliverySeat {
+			_, err := askDeliveryOwner(ctx, conn, verb, body)
+			return err
+		}
+		granted := false
+		for _, v := range broker.VerbsTheControllerActsOnAWarrant {
+			granted = granted || (v.Seat == seat && v.Verb == verb)
+		}
+		if !granted {
+			return fmt.Errorf("%s: %w", a.Verb, errNotGranted)
+		}
+		var answer link.Answer
+		var err error
+		if a.Machine != "" {
+			answer, err = link.AskSeatTool(ctx, conn, seat, verb, a.Machine, body, askWithin)
+		} else {
+			answer, err = link.AskMeshSeatTool(ctx, conn, seat, verb, body, askWithin)
+		}
+		if err != nil {
+			return err
+		}
+		if answer.Error != "" {
+			return fmt.Errorf("%s refused: %s", a.Verb, answer.Error)
+		}
+		return nil
+	}
+}
+
+// routerRecordOf reads the router's record of one of the controller's asks, under its name, and answers
+// how it ended when it did: the bucket is the one the asks seat's declarer names as its records.
+func routerRecordOf(conn *nats.Conn, inv *inventory.Inventory) func(ctx context.Context, id string) (*asks.Warrant, error) {
+	return func(ctx context.Context, id string) (*asks.Warrant, error) {
+		bucket, err := asksRecords(ctx, inv)
+		if err != nil || bucket == "" {
+			return nil, err
+		}
+		reply, err := conn.RequestWithContext(ctx, "$JS.API.DIRECT.GET.KV_"+bucket+".$KV."+bucket+"."+askerName+"."+id, nil)
+		if err != nil {
+			return nil, err
+		}
+		if reply.Header.Get("Status") != "" {
+			return nil, nil // none, or not readable: the event says it
+		}
+		var rec struct {
+			State   string        `json:"state"`
+			Warrant *asks.Warrant `json:"warrant"`
+		}
+		if json.Unmarshal(reply.Data, &rec) != nil || rec.State == "open" || rec.Warrant == nil {
+			return nil, nil
+		}
+		return rec.Warrant, nil
+	}
+}
+
+// asksRecords is the bucket the asks seat's declarer keeps its record of asks in.
+func asksRecords(ctx context.Context, inv catalogueReader) (string, error) {
+	declared, err := inv.Catalogue(ctx)
+	if err != nil {
+		return "", err
+	}
+	for _, m := range declared {
+		for _, s := range m.DefinesSeats {
+			if s.Name == broker.AsksSeat && len(s.Records) > 0 {
+				return broker.BucketName(m.Module, s.Records[0]), nil
+			}
+		}
+	}
+	return "", nil
+}
+
+// routerHereIn says whether a module declaring the asks seat, with its ask named by its caller, is assigned:
+// without it nothing takes an ask, and asking would only fill a queue nobody reads.
+func routerHereIn(inv *inventory.Inventory) func(ctx context.Context) (bool, error) {
+	return func(ctx context.Context) (bool, error) {
+		entries, err := inv.Catalogued(ctx)
+		if err != nil {
+			return false, err
+		}
+		for _, e := range entries {
+			for _, s := range e.Manifest.DefinesSeats {
+				if s.Name == broker.AsksSeat && s.NamedByCaller("ask") && len(e.On) > 0 {
+					return true, nil
+				}
+			}
+		}
+		return false, nil
+	}
+}
+
+// grantHeldIn says whether the bus holds the controller's grant to ask (novox/hq issue 353), judged on the two
+// facts that make it so, and failing closed on each:
+//
+//  1. **composed**: the user list the mesh composes now grants the controller itself to publish its ask
+//     (controllerMayAsk) — the controller's own grant, not whether any user of the list changed;
+//  2. **in force**: the bus's own module, on the machine holding the bus, says the user list there allows it
+//     and the server reloaded after that list was written (the nats module's `nats_user_can`, `in_force`) — a
+//     list sent is not a list the bus enforces until it reloads.
+//
+// Anything that cannot be worked out is not held, with why, so the conditions that need the operator are said
+// as undelivered rather than asked into a refusal.
+func grantHeldIn(open *stores, conn *nats.Conn) func(ctx context.Context) (bool, string, error) {
+	return grantHeldBy(composedGrantIn(open), busGrantIn(open, conn), time.Now)
+}
+
+// grantJudge is one of the two facts: whether it holds, and why not.
+type grantJudge func(ctx context.Context) (bool, string, error)
+
+// grantHeldBy is the judgement over the two facts, remembered for grantLookEvery: composing the list resolves
+// the bus's machine whole, and asking the bus's module is a call.
+func grantHeldBy(composed, inForce grantJudge, now func() time.Time) func(ctx context.Context) (bool, string, error) {
+	var mu sync.Mutex
+	var at time.Time
+	var held bool
+	var why string
+	return func(ctx context.Context) (bool, string, error) {
+		mu.Lock()
+		defer mu.Unlock()
+		if !at.IsZero() && now().Sub(at) < grantLookEvery {
+			return held, why, nil
+		}
+		held, why = judgeGrant(ctx, composed, inForce)
+		at = now()
+		return held, why, nil
+	}
+}
+
+// judgeGrant is held only when both facts hold; an error is a fact not known, never a yes. A fact that holds
+// with a caveat (a reload not confirmed) gives that caveat as the why of a yes.
+func judgeGrant(ctx context.Context, composed, inForce grantJudge) (bool, string) {
+	var caveat []string
+	for _, fact := range []struct {
+		judge grantJudge
+		what  string
+	}{{composed, "whether the mesh composes the controller a grant to ask"}, {inForce, "whether the bus enforces it"}} {
+		if fact.judge == nil {
+			return false, fact.what + " is not judged here"
+		}
+		ok, why, err := fact.judge(ctx)
+		if err != nil {
+			return false, fact.what + " could not be worked out: " + err.Error()
+		}
+		if !ok {
+			return false, why
+		}
+		if why != "" {
+			caveat = append(caveat, why)
+		}
+	}
+	return true, strings.Join(caveat, "; ")
+}
+
+// controllerMayAsk says whether the controller's own grant, as composed from these records, lets it publish its
+// ask (ADR 0259 §3: composed while a router that takes asks under its asker's name is assigned).
+func controllerMayAsk(records broker.Records) (bool, error) {
+	users, err := broker.Users(records)
+	if err != nil {
+		return false, err
+	}
+	for _, u := range users {
+		if u.Kind != broker.KindController {
+			continue
+		}
+		perms, err := broker.PermissionsFor(u)
+		if err != nil {
+			return false, err
+		}
+		return broker.MayPublish(perms, asks.AskSubject(askerName)), nil
+	}
+	return false, errors.New("the composition holds no controller")
+}
+
+// composedGrantIn is the first fact, from the mesh's records.
+func composedGrantIn(open *stores) grantJudge {
+	return func(ctx context.Context) (bool, string, error) {
+		if open == nil || open.inventory == nil {
+			return false, "", errors.New("the mesh's records are not open")
+		}
+		records, err := open.inventory.BusRecords(ctx)
+		if err != nil {
+			return false, "", err
+		}
+		may, err := controllerMayAsk(records)
+		if err != nil || may {
+			return may, "", err
+		}
+		return false, "the mesh composes the controller no grant to ask: no router that takes asks under its " +
+			"asker's name is assigned", nil
+	}
+}
+
+// busGrantIn is the second fact, asked of the bus's own module on the machine holding the bus, with the check
+// main made before it (novox/hq issue 353, PR 186: is the user list sent to the bus's machine the one composed
+// now) kept for the cases the module's word does not settle.
+func busGrantIn(open *stores, conn *nats.Conn) grantJudge {
+	ask := func(ctx context.Context) (string, json.RawMessage, error) {
+		if open == nil || open.inventory == nil || conn == nil {
+			return "", nil, errors.New("the mesh's records or the bus are not open")
+		}
+		holders, err := seatHolders(ctx, open.inventory)
+		if err != nil {
+			return "", nil, err
+		}
+		h, held := holders[theBrokerSeat]
+		if !held || h.Node == "" || h.Module == "" {
+			return "", nil, nil
+		}
+		a, err := link.AskModuleToolOn(ctx, conn, h.Module, busUserCanTool, h.Node, map[string]any{
+			"user": broker.ControllerName, "action": "publish", "subject": asks.AskSubject(askerName)}, 15*time.Second)
+		if err != nil {
+			return h.Node, nil, err
+		}
+		if a.Error != "" {
+			return h.Node, nil, errors.New(a.Error)
+		}
+		return h.Node, a.Result, nil
+	}
+	list := func(ctx context.Context) (busListState, error) {
+		if open == nil || open.inventory == nil {
+			return busListState{}, errors.New("the mesh's records are not open")
+		}
+		s, err := brokerListState(ctx, open, nil)
+		if err != nil || s.Machine == "" || !s.Behind {
+			return s, err
+		}
+		step, err := busHeld(ctx, open.inventory, []string{s.Machine})
+		if err != nil {
+			return busListState{}, err
+		}
+		s.BusStep = step[s.Machine]
+		return s, nil
+	}
+	return busGrantBy(ask, list)
+}
+
+// busListState is the user list on the bus's machine as the controller's record knows it: whether the list
+// sent there is behind the one composed now, why it could not be composed, and the bus step a send there waits
+// on (that machine cannot be pushed until a person's `bus upgrade`).
+type busListState struct {
+	Machine    string
+	Behind     bool
+	Uncomposed error
+	BusStep    string
+}
+
+// remedy is the one thing that sends the bus's machine the list composed now: the plan's own reason when it
+// cannot be composed, the bus upgrade while sends there wait on it, and otherwise a push of that machine.
+func (s busListState) remedy(node string) string {
+	if s.Machine != "" {
+		node = s.Machine
+	}
+	switch {
+	case s.Uncomposed != nil:
+		return fmt.Sprintf("the user list for %s cannot be composed (%v); `plan %s` says what to fix first",
+			node, s.Uncomposed, node)
+	case s.BusStep != "":
+		return fmt.Sprintf("sends to %s wait on the bus's planned step, so a push will not carry it: %s", node, s.BusStep)
+	}
+	return fmt.Sprintf("`push %s` carries it", node)
+}
+
+// busGrantBy judges the bus's word, and names for each way it is not held the one thing that makes it held:
+//
+//   - **in force**: held;
+//   - **allowed, from a module older than `in_force`**: held, with the caveat that the reload is not confirmed.
+//     The file allows the publish, and the bus reloads within about 5 s of a change to it, so the worst case is
+//     one ask refused in those seconds, which is asked again (issue 369). The list check is not consulted:
+//     while a bus step is pending the bus's machine cannot be pushed, so any change to the composed list would
+//     read as behind for good and silence every ask until a person's bus upgrade (the review of PR 188);
+//   - **allowed, written, not reloaded** (the module gives both times): wait about 5 s;
+//   - **allowed, in force not known** (the module could not read a time): what is not known, said;
+//   - **not allowed, or the module cannot answer**: the list check decides — the remedy that sends the list
+//     when it is behind (busListState.remedy), and, for a module that cannot answer, held while the list sent
+//     is current, as main judged it.
+//
+// ask answers the machine holding the bus and its module's answer ("" when nothing holds the bus); list is the
+// record's word on the list sent to that machine.
+func busGrantBy(ask func(ctx context.Context) (string, json.RawMessage, error),
+	list func(ctx context.Context) (busListState, error)) grantJudge {
+	return func(ctx context.Context) (bool, string, error) {
+		node, raw, askErr := ask(ctx)
+		if askErr == nil && node == "" {
+			return false, "no module holds the bus, so nothing says what it enforces", nil
+		}
+		var answer busAnswer
+		if askErr == nil {
+			if answer, askErr = readBusAnswer(raw); askErr != nil {
+				askErr = fmt.Errorf("its answer could not be read: %w", askErr)
+			}
+		}
+		if askErr != nil {
+			if node == "" {
+				node = "the bus's machine"
+			}
+			s, err := list(ctx)
+			if err != nil {
+				return false, "", fmt.Errorf("the bus module on %s could not answer (%v), and whether the list sent "+
+					"there is the one composed now could not be worked out: %w", node, askErr, err)
+			}
+			if s.Behind {
+				return false, fmt.Sprintf("the bus module on %s could not answer (%v), and the user list sent there is "+
+					"behind what the mesh composes; %s", node, askErr, s.remedy(node)), nil
+			}
+			return true, fmt.Sprintf("the bus module on %s could not answer (%v); judged by the user list sent there, "+
+				"which is the one composed now", node, askErr), nil
+		}
+		notAllowed := func(older string) (bool, string, error) {
+			s, err := list(ctx)
+			if err != nil {
+				return false, "", fmt.Errorf("the user list on %s does not allow the controller to ask%s, and whether "+
+					"the list sent there is the one composed now could not be worked out: %w", node, older, err)
+			}
+			if s.Behind {
+				return false, fmt.Sprintf("the user list on %s does not allow the controller to ask%s: it is behind "+
+					"what the mesh composes; %s", node, older, s.remedy(node)), nil
+			}
+			return false, fmt.Sprintf("the user list on %s does not allow the controller to ask%s, though the list "+
+				"sent there is the one composed now; %s again", node, older, s.remedy(node)), nil
+		}
+		switch {
+		case answer.InForce == nil && answer.Allowed:
+			return true, fmt.Sprintf("the user list on %s allows the controller to ask, but its reload is not "+
+				"confirmed: the bus module there is older than the answer whether a grant is in force, and the bus "+
+				"upgrade (`bus upgrade`) carries one that confirms it", node), nil
+		case answer.InForce == nil:
+			return notAllowed(" (the bus module there is older than the answer whether a grant is in force)")
+		case !answer.Allowed:
+			return notAllowed("")
+		case *answer.InForce:
+			return true, "", nil
+		case answer.FileWritten != "" && answer.ServerLoaded != "":
+			return false, fmt.Sprintf("the bus on %s has the controller's grant to ask written (%s) but has not "+
+				"reloaded since (last load %s); it reloads in place within about 5 s, so nothing is to be done but wait",
+				node, answer.FileWritten, answer.ServerLoaded), nil
+		}
+		why := answer.Why
+		if why == "" {
+			why = "it gives no reason"
+		}
+		return false, fmt.Sprintf("the user list on %s allows the controller to ask, but whether the bus enforces it "+
+			"is not known: %s", node, why), nil
+	}
+}
+
+// busUserCanTool is the bus module's answer to whether a user may do something, and whether it is in force.
+const busUserCanTool = "nats_user_can"
+
+// busAnswer is the bus module's answer to busUserCanTool; InForce is nil from a module older than that field,
+// and FileWritten and ServerLoaded are given only when it could read both times (mesh-catalog's nats InForce).
+type busAnswer struct {
+	Allowed      bool   `json:"allowed"`
+	InForce      *bool  `json:"in_force"`
+	Why          string `json:"why"`
+	FileWritten  string `json:"file_written"`
+	ServerLoaded string `json:"server_loaded"`
+}
+
+func readBusAnswer(raw json.RawMessage) (busAnswer, error) {
+	var answer busAnswer
+	err := json.Unmarshal(raw, &answer)
+	return answer, err
+}
+
+// grantLookEvery is how often the bus's user list is judged against the one its machine was last sent.
+const grantLookEvery = 30 * time.Second
+
+// channelsIn is what the channels are now, as a fingerprint: each module claiming a kind of the channel
+// bench, where, promising what, and whether of its own account. An ask the router refused is asked again
+// once this changes.
+func channelsIn(inv *inventory.Inventory) func(ctx context.Context) string {
+	return func(ctx context.Context) string {
+		entries, err := inv.Catalogued(ctx)
+		if err != nil {
+			return ""
+		}
+		var parts []string
+		for _, e := range entries {
+			for _, c := range e.Manifest.Claims {
+				if c.Kind == "" || !catalogue.KindedBenches[c.Name] {
+					continue
+				}
+				on := append([]string(nil), e.On...)
+				sort.Strings(on)
+				caps := append([]string(nil), c.Capabilities...)
+				sort.Strings(caps)
+				parts = append(parts, fmt.Sprintf("%s/%s=%s@%s[%s]own:%t", c.Name, c.Kind, e.Manifest.Module,
+					strings.Join(on, ","), strings.Join(caps, ","), e.Manifest.RunsAs != ""))
+			}
+		}
+		sort.Strings(parts)
+		return strings.Join(parts, ";")
+	}
+}
+
+// startAsking makes the serving controller's asker and hands it the router's words.
+func startAsking(ctx context.Context, open *stores, server *link.Server, conn *nats.Conn, keeper *conditions.Keeper) {
+	js, err := jetstream.New(conn)
+	if err != nil {
+		fmt.Printf("the operator cannot be asked: %v\n", err)
+		return
+	}
+	a := servingAsker(open, conn, js, keeper)
+	if err := server.Decides(a); err != nil {
+		fmt.Printf("the operator's answers cannot be heard, so nothing is asked: %v\n", err)
+		return
+	}
+	askerFrom = a
+	go a.keep(ctx)
+}
+
+// servingAsker is the serving controller's asker, wired to the mesh: what it reads, publishes, performs and
+// records, and the judgements it asks by — the bus's grant to ask among them (novox/hq issue 353).
+func servingAsker(open *stores, conn *nats.Conn, js jetstream.JetStream, keeper *conditions.Keeper) *asker {
+	return &asker{
+		open: keeper.Open,
+		silence: func(ctx context.Context, key string, d time.Duration, by, why string) error {
+			_, err := keeper.Silence(ctx, key, d, by, why)
+			return err
+		},
+		store: busAsked{conn: conn},
+		publish: func(ctx context.Context, subject string, body []byte, id string) error {
+			_, err := js.Publish(ctx, subject, body, jetstream.WithMsgID(id))
+			return err
+		},
+		call: callAction(conn),
+		// A proposed settings layer is set by this controller itself on the warrant (novox/hq ADR 0277).
+		setLayer: setLayerIn(open),
+		record: func(ctx context.Context, act link.HandAct) error {
+			_, err := link.RecordHandAct(ctx, conn, act)
+			return err
+		},
+		routerRecord: routerRecordOf(conn, open.inventory),
+		routerHere:   routerHereIn(open.inventory),
+		grantHeld:    grantHeldIn(open, conn),
+		channels:     channelsIn(open.inventory),
+		raise: func(ctx context.Context, obs []conditions.Observation) error {
+			return keeper.Reconcile(ctx, sourceAsker, obs)
+		},
+		now:  time.Now,
+		logf: func(format string, args ...any) { fmt.Printf(format+"\n", args...) },
+	}
+}

cmd/mesh-controller/awaiting_push_integration_test.go

@@ -0,0 +1,193 @@
+//go:build integration
+
+package main
+
+import (
+	"errors"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/overlay"
+)
+
+func TestAModuleAssignedAndNotPushedIsAwaitingAPushNotUncomposable(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	register(t, open, aKeeper())
+	pushedBy(t, open, "laptop") // the machine was pushed before; then the module is assigned
+	if _, err := assign(ctx, open, "laptop", "keeper"); err != nil {
+		t.Fatal(err)
+	}
+
+	// The read the rest of the mesh asks still refuses it, with the composer's typed error: nothing
+	// can be compared about a secret that does not exist (status), and nothing here string-matches.
+	plan, settings, err := planFor(ctx, open, "laptop")
+	if err != nil {
+		t.Fatal(err)
+	}
+	gens, err := generators(ctx, open)
+	if err != nil {
+		t.Fatal(err)
+	}
+	_, err = declarationWith(ctx, open, "laptop", plan, settings, gens, Reading)
+	var notMade *catalogue.NotMadeError
+	if !errors.As(err, &notMade) || notMade.Module != "keeper" || notMade.Name != "repository" {
+		t.Fatalf("a read composition did not say which secret is not made, typed: %v", err)
+	}
+	// Foreseen, it composes, names what the push makes, and made nothing.
+	foreseen, err := declarationWith(ctx, open, "laptop", plan, settings, gens, Foreseeing)
+	if err != nil || len(foreseen.foreseen) != 1 || foreseen.foreseen[0] != "keeper/repository" {
+		t.Fatalf("foreseen: %v %v", foreseen.foreseen, err)
+	}
+	if _, held, err := open.inventory.ModuleSecretIfIssued(ctx, "laptop", "keeper", "repository"); err != nil || held {
+		t.Fatalf("asking ahead of the push made the secret (held %v, %v)", held, err)
+	}
+
+	// Within the bound: nothing at all — no urgent, no warning, nobody notified.
+	if got := d1(t, open); len(got) != 0 {
+		t.Fatalf("a machine waiting for a push raised %+v", got)
+	}
+
+	// Past the bound: a warning, not urgent, saying what the push will make.
+	before := awaitingPushBound
+	awaitingPushBound = -time.Minute
+	t.Cleanup(func() { awaitingPushBound = before })
+	got := d1(t, open)
+	if len(got) != 1 || got[0].Key() != "machine.laptop.awaiting-push" || got[0].Severity != conditions.Warning ||
+		!strings.Contains(got[0].Summary, "keeper/repository") || !strings.Contains(got[0].Summary, "push laptop") {
+		t.Fatalf("a machine left un-pushed past the bound: %+v", got)
+	}
+
+	// Pushed: the secret is made and D1 says nothing.
+	pushedBy(t, open, "laptop")
+	if got := d1(t, open); len(got) != 0 {
+		t.Fatalf("a pushed machine still raised %+v", got)
+	}
+}
+
+func TestASecretThePushCannotMakeIsStillUncomposable(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	register(t, open, aTalker())
+	if _, err := assign(ctx, open, "laptop", "talker"); err != nil {
+		t.Fatal(err)
+	}
+	got := d1(t, open)
+	if len(got) != 1 || got[0].Key() != "machine.laptop.uncomposable" || got[0].Severity != conditions.Urgent ||
+		!strings.Contains(got[0].Summary, "module issue talker --node laptop") {
+		t.Fatalf("a push that will be refused was not said urgently: %+v", got)
+	}
+
+	// And a machine whose composition fails for anything else, with a secret waiting beside it, is
+	// uncomposable for that — the stand-in hides nothing.
+	register(t, open, aKeeper())
+	if _, err := assign(ctx, open, "anchor", "keeper"); err != nil {
+		t.Fatal(err)
+	}
+	one, two := rivals()
+	register(t, open, one)
+	register(t, open, two)
+	_, _ = assign(ctx, open, "anchor", "rival-one")
+	_, _ = assign(ctx, open, "anchor", "rival-two")
+	keys := map[string]conditions.Severity{}
+	for _, o := range d1(t, open) {
+		keys[o.Key()] = o.Severity
+	}
+	if keys["machine.anchor.uncomposable"] != conditions.Urgent {
+		t.Fatalf("a real failure beside a waiting secret: %v", keys)
+	}
+}
+
+func TestAGivenSecretUnderAnOldKeyIsNotForeseen(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	register(t, open, aKeeper())
+	if _, err := assign(ctx, open, "laptop", "keeper"); err != nil {
+		t.Fatal(err)
+	}
+	if err := open.inventory.AcceptSecretForModule(ctx, "laptop", "keeper", "repository", "given"); err != nil {
+		t.Fatal(err)
+	}
+	record, err := open.inventory.NodeByName(ctx, "laptop")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := open.inventory.RecordSealingKey(ctx, record.ID, aPublicKey(t)); err != nil {
+		t.Fatal(err)
+	}
+	got := d1(t, open)
+	if len(got) != 1 || got[0].Key() != "machine.laptop.uncomposable" || !strings.Contains(got[0].Summary, "issue it again") {
+		t.Fatalf("a given secret under an old key: %+v", got)
+	}
+}
+
+func TestAMachineAwaitsAPushSinceItsOldestAssignmentSinceTheLastSend(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	register(t, open, aKeeper())
+	pushedBy(t, open, "laptop")
+	sent := time.Now()
+	since, err := open.inventory.AwaitingSince(ctx, "laptop")
+	if err != nil || since.After(sent) {
+		t.Fatalf("nothing assigned since the send: waiting since %v (%v), the send was before %v", since, err, sent)
+	}
+	if _, err := assign(ctx, open, "laptop", "keeper"); err != nil {
+		t.Fatal(err)
+	}
+	since, err = open.inventory.AwaitingSince(ctx, "laptop")
+	if err != nil || since.Before(sent.Add(-time.Second)) {
+		t.Fatalf("assigned after the send: waiting since %v (%v), not from the assignment", since, err)
+	}
+}
+
+func TestALastSendIsReadFromTheSendAndTheReport(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	// What a machine was sent is read from the commits its assignments name (issue 1109): a module is carried by a send only
+	// when it was built from a commit, and a hand send on a machine with nothing assigned leaves no key to mark unknown.
+	if err := open.inventory.RegisterModule(ctx, aKeeper(), inventory.Source{BuiltFrom: "c-keeper"}); err != nil {
+		t.Fatal(err)
+	}
+	record, err := open.inventory.NodeByName(ctx, "laptop")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := open.inventory.RecordSent(ctx, record.ID, "carried", map[string]string{overlay.Name: "c-overlay"}); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := assign(ctx, open, "laptop", "keeper"); err != nil {
+		t.Fatal(err)
+	}
+	sends, err := readDeliveries(ctx, open.inventory)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if sends["laptop"].settled("keeper", time.Now()) {
+		t.Fatal("a holder assigned and not pushed is expected to answer")
+	}
+	if !sends["laptop"].settled(overlay.Name, time.Now().Add(time.Hour)) {
+		t.Fatal("a module the machine was sent long ago is not expected to answer")
+	}
+	pushedBy(t, open, "laptop")
+	sends, err = readDeliveries(ctx, open.inventory)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if sends["laptop"].settled("keeper", time.Now()) {
+		t.Fatal("pushed a moment ago and not reported, a holder is already expected")
+	}
+	if !sends["laptop"].settled("keeper", time.Now().Add(reportGrace+time.Minute)) {
+		t.Fatal("pushed past the grace, a holder is not expected")
+	}
+	if _, ok := sends["laptop"].carried["keeper"]; !ok {
+		t.Fatalf("the send's builds do not carry keeper: %v", sends["laptop"].carried)
+	}
+	pushedAndApplied(t, open, "laptop")
+	if sends, err = readDeliveries(ctx, open.inventory); err != nil || !sends["laptop"].settled("keeper", time.Now()) {
+		t.Fatalf("pushed and reported applied, a holder is not expected to answer (%v)", err)
+	}
+}

cmd/mesh-controller/awaiting_push_test.go

@@ -0,0 +1,129 @@
+package main
+
+import (
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// Between `assign` and `push` a module's own secrets are not made yet: the push makes them. D1 composed
+// the machine's declaration without making anything, failed on the missing secret, and raised an urgent
+// "nothing can be sent to <machine>" — seen live on 2026-10-06, a desktop notification for a machine
+// the next push sent to without a word (novox/hq issue 275). D1 now composes as the push would, with a
+// stand-in for what the push makes: pending, not broken, and said only past a bound, as a warning.
+
+// aKeeper is a module with an own secret the mesh makes — a backup repository's password.
+func aKeeper() catalogue.Manifest {
+	return catalogue.Manifest{Module: "keeper", Version: "1",
+		OwnSecrets: catalogue.OwnSecrets{"repository": {Path: "/var/lib/mesh/keeper/repository"}},
+		Resources: []map[string]any{
+			{"id": "state", "type": "directory", "path": "/var/lib/mesh/keeper", "mode": "0700"},
+		}}
+}
+
+// pushedBy records a send to a machine as a push does — composed on the send path, so its own secrets
+// are made — without a bus to carry it.
+func pushedBy(t *testing.T, open *stores, node string) string {
+	t.Helper()
+	ctx := t.Context()
+	plan, settings, err := planFor(ctx, open, node)
+	if err != nil {
+		t.Fatal(err)
+	}
+	declared, err := declarationFor(ctx, open, node, plan, settings)
+	if err != nil {
+		t.Fatal(err)
+	}
+	body, err := declared.Body()
+	if err != nil {
+		t.Fatal(err)
+	}
+	record, err := open.inventory.NodeByName(ctx, node)
+	if err != nil {
+		t.Fatal(err)
+	}
+	digest := digestOf(body)
+	// A push records the build of each module it carries (plan.go, Allocating); a module is carried by a send only when it was
+	// built from a commit, for what a machine was sent is read from the commits its assignments name (issue 1109).
+	builds := declared.Builds
+	if builds == nil {
+		current, err := open.inventory.CurrentBuilds(ctx)
+		if err != nil {
+			t.Fatal(err)
+		}
+		names := make([]string, 0, len(plan.Modules))
+		for _, m := range plan.Modules {
+			names = append(names, m.Module)
+		}
+		builds = carriedBuilds(names, nil, current, nil)
+	}
+	if err := open.inventory.RecordSent(ctx, record.ID, digest, builds); err != nil {
+		t.Fatal(err)
+	}
+	return digest
+}
+
+// pushedAndApplied is pushedBy, and the machine reporting it applied that declaration.
+func pushedAndApplied(t *testing.T, open *stores, node string) {
+	t.Helper()
+	digest := pushedBy(t, open, node)
+	record, err := open.inventory.NodeByName(t.Context(), node)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := open.inventory.RecordDoing(t.Context(), record.ID, inventory.Doing{
+		Outcome: inventory.OutcomeApplied, Declared: digest}); err != nil {
+		t.Fatal(err)
+	}
+}
+
+// d1 runs D1 once.
+func d1(t *testing.T, open *stores) []conditions.Observation {
+	t.Helper()
+	got, err := probeDeclarations(t.Context(), &doctor{open: open})
+	if err != nil {
+		t.Fatal(err)
+	}
+	return got
+}
+
+// **THE WINDOW, REPRODUCED**: assigned and not pushed, a module whose own secret the push makes is
+// waiting, not uncomposable; past the bound it is a warning naming what the push makes; pushed, nothing.
+
+// **A REAL FAILURE IS STILL URGENT**: a secret the push would be refused on is not one it will make.
+// A bus credential nobody issued (issue 203) fails the push, so D1 says it — urgent, in the push's words.
+
+// A given secret sealed to a key the machine no longer has is not the mesh's to make again: the push is
+// refused on it, so D1 is too.
+
+// The bound is read from when the machine began waiting: the oldest assignment since its last send.
+
+// **D3 AND D13 WAIT FOR THE SEND**: a holder is expected to answer on a machine once the machine was sent
+// it and had time to report — never between assign and push.
+func TestAHolderIsExpectedOnlyOnceSentAndReported(t *testing.T) {
+	now := time.Now()
+	sent := now.Add(-time.Minute)
+	long := now.Add(-time.Hour)
+	cases := []struct {
+		name string
+		send lastSend
+		want bool
+	}{
+		{"never sent", lastSend{}, false},
+		{"sent without it", lastSend{sent: &long, current: true, carried: map[string]string{"other": "c"}}, false},
+		{"sent with it, not reported yet", lastSend{sent: &sent, carried: map[string]string{"keeper": "c"}}, false},
+		{"sent with it and reported", lastSend{sent: &sent, current: true, carried: map[string]string{"keeper": "c"}}, true},
+		{"sent with it long ago, never reported", lastSend{sent: &long, carried: map[string]string{"keeper": "c"}}, true},
+		{"sent before builds were kept", lastSend{sent: &long, current: true}, true},
+	}
+	for _, c := range cases {
+		if got := c.send.settled("keeper", now); got != c.want {
+			t.Errorf("%s: settled %v, want %v", c.name, got, c.want)
+		}
+	}
+}
+
+// And through the stores: assigned, not in the last send; pushed and reported, carried and settled.

cmd/mesh-controller/backups_before_send_integration_test.go

@@ -0,0 +1,308 @@
+//go:build integration
+
+package main
+
+import (
+	"encoding/json"
+	"os"
+	"strings"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/nats-io/nats.go"
+	"github.com/novox/mesh-controller/internal/broker"
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+	"github.com/novox/mesh-controller/internal/testbus"
+)
+
+// aBackupSeatOnTheBus is one machine's node-backup holder as a test makes it: it counts the `now` asks it hears and
+// answers `backed-up` with the last night it is told (novox/hq ADR 0404).
+type aBackupSeatOnTheBus struct {
+	mu    sync.Mutex
+	nows  []string
+	night map[string]any // module → lastNight
+}
+
+func (f *aBackupSeatOnTheBus) serve(t *testing.T, conn *nats.Conn, node string) {
+	t.Helper()
+	reply := func(m *nats.Msg, result any) {
+		body, _ := json.Marshal(map[string]any{"result": result, "error": "", "node": node})
+		_ = m.Respond(body)
+	}
+	now, err := conn.Subscribe(link.NodeSeatToolSubject(catalogue.BackupSeat, "now", node), func(m *nats.Msg) {
+		var a struct {
+			Module string `json:"module"`
+		}
+		_ = json.Unmarshal(m.Data, &a)
+		f.mu.Lock()
+		f.nows = append(f.nows, a.Module)
+		f.mu.Unlock()
+		reply(m, map[string]any{"started": a.Module})
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	read, err := conn.Subscribe(link.NodeSeatToolSubject(catalogue.BackupSeat, "backed-up", node), func(m *nats.Msg) {
+		f.mu.Lock()
+		defer f.mu.Unlock()
+		var out []map[string]any
+		for module, n := range f.night {
+			out = append(out, map[string]any{"module": module, "lastNight": n})
+		}
+		reply(m, out)
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { _ = now.Unsubscribe(); _ = read.Unsubscribe() })
+	if err := conn.Flush(); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func (f *aBackupSeatOnTheBus) answers(module string, ok bool, words string) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.night = map[string]any{module: map[string]any{"ok": ok, "at": time.Now().UTC().Add(time.Second), "error": words}}
+}
+
+func (f *aBackupSeatOnTheBus) asks() int {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	return len(f.nows)
+}
+
+// Acceptance test 3 of design 47, on the controller's side: a delivery plan that moves a module keeping data waits
+// for its backups on both machines before it asks a build; a backup that fails holds it, with the machine, the
+// module and the backup's words, and a condition says the same; the verb the delivery's release calls asks the
+// backups again, and the plan goes on. One bus and one store for the scenarios.
+func TestADeliveryThatMovesABackedUpModuleWaitsForItsBackupAndAFailedOneHoldsItAndIsSaid(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	inv := open.inventory
+	asked := asksRecorded(t)
+	js, err := broker.Dial(testbus.URL(t))
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(js.Close)
+	before := handActConn
+	handActConn = js.Conn()
+	t.Cleanup(func() { handActConn = before })
+
+	if _, err := inv.SeedSeats(ctx, catalogue.DefaultSeats()); err != nil {
+		t.Fatal(err)
+	}
+	register(t, open, catalogue.Manifest{Module: "keeper", Version: "1",
+		Claims: []catalogue.Claim{{Name: catalogue.BackupSeat, Scope: catalogue.ScopeNode, Serves: []string{"backed-up", "now", "restore"}}}})
+	notes, err := catalogue.ParseManifest([]byte(`{"module":"notes","version":"1","data":{"own":[` +
+		`{"id":"files","path":"${dir:files}","class":"valuable","why":"people's notes"}]},` +
+		`"resources":[{"id":"files","type":"directory"}]}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := inv.RegisterModule(ctx, notes, inventory.Source{Repository: "novox/mesh-catalog", Seat: "git",
+		Path: "modules/notes", Ref: "main", BuiltFrom: "c0", Head: "c0"}); err != nil {
+		t.Fatal(err)
+	}
+	for _, node := range []string{"anchor", "laptop"} {
+		if _, err := assign(ctx, open, node, "keeper"); err != nil {
+			t.Fatal(err)
+		}
+		if _, err := assign(ctx, open, node, "notes"); err != nil {
+			t.Fatal(err)
+		}
+	}
+	seats := map[string]*aBackupSeatOnTheBus{"anchor": {}, "laptop": {}}
+	for node, s := range seats {
+		s.serve(t, js.Conn(), node)
+	}
+	// Short waits: the bound and the look are variables, so nothing here waits for the minutes of a real backup.
+	wasWithin, wasEvery := backupsWithin, backupsPollEvery
+	backupsWithin, backupsPollEvery = time.Minute, 10*time.Millisecond
+	t.Cleanup(func() { backupsWithin, backupsPollEvery = wasWithin, wasEvery })
+
+	newPlan := func(id string) {
+		t.Helper()
+		p := inventory.Plan{ID: id, Repository: "novox/mesh-catalog", Branch: "main", Commit: "c1", Created: time.Now().UTC(),
+			State: inventory.PlanBuilding, Tiers: [][]string{{"notes"}}, Modules: map[string]*inventory.PlanModule{"notes": {}}}
+		if err := inv.SavePlan(ctx, &p); err != nil {
+			t.Fatal(err)
+		}
+	}
+	read := func(id string) inventory.Plan {
+		t.Helper()
+		p, err := inv.PlanByID(ctx, id)
+		if err != nil {
+			t.Fatal(err)
+		}
+		return p
+	}
+
+	// 1. Both machines are asked; while one has not answered, no build is asked.
+	newPlan("plan-one")
+	advancePlans(ctx, open)
+	if seats["anchor"].asks() != 1 || seats["laptop"].asks() != 1 || len(*asked) != 0 {
+		t.Fatalf("asks anchor=%d laptop=%d builds=%v", seats["anchor"].asks(), seats["laptop"].asks(), *asked)
+	}
+	seats["anchor"].answers("notes", true, "")
+	advancePlans(ctx, open)
+	if len(*asked) != 0 || read("plan-one").Backups.State != inventory.BackupPending {
+		t.Fatalf("a tier was asked while a backup was pending: %v %+v", *asked, read("plan-one").Backups)
+	}
+	seats["laptop"].answers("notes", true, "")
+	advancePlans(ctx, open)
+	if len(*asked) != 1 || read("plan-one").Backups.State != inventory.BackupDone {
+		t.Fatalf("the tier was not asked once every backup was done: %v %+v", *asked, read("plan-one").Backups)
+	}
+	finish := read("plan-one")
+	finish.State = inventory.PlanDone
+	if err := inv.SavePlan(ctx, &finish); err != nil {
+		t.Fatal(err)
+	}
+
+	// 2. A backup that fails holds the plan: not failed, nothing asked, the words kept, a condition raised.
+	seats["anchor"].night, seats["laptop"].night = nil, nil
+	newPlan("plan-two")
+	advancePlans(ctx, open)
+	seats["anchor"].answers("notes", true, "")
+	seats["laptop"].answers("notes", false, "no space left on device")
+	advancePlans(ctx, open)
+	held := read("plan-two")
+	if held.State != inventory.PlanBuilding || held.Backups.State != inventory.BackupFailed || len(*asked) != 1 {
+		t.Fatalf("the plan was not held: %s %+v builds=%v", held.State, held.Backups, *asked)
+	}
+	var failed *inventory.PlanBackup
+	for i := range held.Backups.Asked {
+		if held.Backups.Asked[i].State == inventory.BackupFailed {
+			failed = &held.Backups.Asked[i]
+		}
+	}
+	if failed == nil || failed.Machine != "laptop" || failed.Module != "notes" || failed.Words != "no space left on device" ||
+		strings.Contains(held.Note, "tried again") {
+		t.Fatalf("the failed backup: %+v note=%q", failed, held.Note)
+	}
+	advancePlans(ctx, open) // not retried on the next look
+	if again := read("plan-two"); again.Backups.State != inventory.BackupFailed || len(*asked) != 1 ||
+		seats["laptop"].asks() != 2 {
+		t.Fatalf("a held plan was asked again by itself: %+v builds=%v asks=%d", again.Backups, *asked, seats["laptop"].asks())
+	}
+	said, err := probeBackupHeld(ctx, &doctor{open: open})
+	if err != nil || len(said) != 1 || said[0].Kind != kindBackupHeld || !strings.Contains(said[0].Said, "no space left on device") {
+		t.Fatalf("the condition: %+v %v", said, err)
+	}
+
+	// 3. The verb the release calls: the failed backup is asked again, and only it, and the plan goes on.
+	seats["laptop"].answers("notes", false, "no space left on device")
+	if err := deliveryCommand(ctx, []string{"backups-again", "plan-two", "--why", "a person released it", "--by",
+		"mesh-delivery for jochen"}); err != nil {
+		t.Fatal(err)
+	}
+	if err := deliveryCommand(ctx, []string{"backups-again", "plan-two", "--why", "again"}); err == nil {
+		t.Fatal("a plan with no failed backup was asked again")
+	}
+	seats["laptop"].night = nil
+	advancePlans(ctx, open)
+	if seats["laptop"].asks() != 3 || seats["anchor"].asks() != 2 {
+		t.Fatalf("asked again: laptop=%d anchor=%d", seats["laptop"].asks(), seats["anchor"].asks())
+	}
+	seats["laptop"].answers("notes", true, "")
+	advancePlans(ctx, open)
+	if got := read("plan-two"); got.Backups.State != inventory.BackupDone || len(*asked) != 2 {
+		t.Fatalf("the plan did not go on: %+v builds=%v", got.Backups, *asked)
+	}
+	if said, _ := probeBackupHeld(ctx, &doctor{open: open}); len(said) != 0 {
+		t.Fatalf("the condition stays: %+v", said)
+	}
+}
+
+// Issue 1086: a plan cut from a merge asked its first tier at the cut, so a module keeping data was sent without the
+// backup the plan promised. The cut now takes the backups first (askFirstTierAtCut, batches.go), and the walk's own
+// step asks the tier once they are done.
+func TestAPlanCutFromAMergeOfABackedUpModuleAsksItsBackupAndNotItsTierUntilItIsDone(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	inv := open.inventory
+	settings := t.TempDir() + "/merge-window.json"
+	if err := os.WriteFile(settings, []byte(`{"merge-window": "90s", "merge-window-at-most": "10m"}`), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	t.Setenv(mergeWindowFileVar, settings)
+	everyHeadWaits(t)
+	asked := asksRecorded(t)
+	js, err := broker.Dial(testbus.URL(t))
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(js.Close)
+	before := handActConn
+	handActConn = js.Conn()
+	t.Cleanup(func() { handActConn = before })
+
+	if _, err := inv.SeedSeats(ctx, catalogue.DefaultSeats()); err != nil {
+		t.Fatal(err)
+	}
+	register(t, open, catalogue.Manifest{Module: "keeper", Version: "1",
+		Claims: []catalogue.Claim{{Name: catalogue.BackupSeat, Scope: catalogue.ScopeNode, Serves: []string{"backed-up", "now", "restore"}}}})
+	if err := inv.RegisterModule(ctx, catalogue.Manifest{Module: "mesh-controller", Version: "1"},
+		inventory.Source{Repository: "novox/mesh-controller", Seat: "git", Ref: "main", BuiltFrom: "c0", Head: "c0"}); err != nil {
+		t.Fatal(err)
+	}
+	notes, err := catalogue.ParseManifest([]byte(`{"module":"notes","version":"1","data":{"own":[` +
+		`{"id":"files","path":"${dir:files}","class":"valuable","why":"people's notes"}]},` +
+		`"resources":[{"id":"files","type":"directory"}]}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := inv.RegisterModule(ctx, notes, inventory.Source{Repository: "novox/notes", Seat: "git", Ref: "main",
+		BuiltFrom: "c0", Head: "c0"}); err != nil {
+		t.Fatal(err)
+	}
+	for _, m := range []string{"keeper", "notes"} {
+		if _, err := assign(ctx, open, "anchor", m); err != nil {
+			t.Fatal(err)
+		}
+	}
+	seat := &aBackupSeatOnTheBus{}
+	seat.serve(t, js.Conn(), "anchor")
+	wasWithin, wasEvery := backupsWithin, backupsPollEvery
+	backupsWithin, backupsPollEvery = time.Minute, 10*time.Millisecond
+	t.Cleanup(func() { backupsWithin, backupsPollEvery = wasWithin, wasEvery })
+
+	// 1. A merge of notes is heard and its window closes: the batch is cut through cutBatch.
+	hear(t, open, repoMerge("notes", "c-notes", t0), t0.Add(time.Second))
+	cutAt(t, open, t0.Add(time.Second+90*time.Second))
+	ws, _ := walks(t, open)
+	if len(ws) != 1 {
+		t.Fatalf("%d walk(s)", len(ws))
+	}
+	// 2. Right after the cut no tier is asked, the record has anchor/notes pending, the seat heard one `now`.
+	cut, err := inv.PlanByID(ctx, ws[0].ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(*asked) != 0 || askedInTier(cut) {
+		t.Fatalf("the first tier was asked at the cut: %v %+v", *asked, cut.Modules)
+	}
+	if cut.Backups == nil || cut.Backups.State != inventory.BackupPending || len(cut.Backups.Asked) != 1 ||
+		cut.Backups.Asked[0].Machine != "anchor" || cut.Backups.Asked[0].Module != "notes" {
+		t.Fatalf("the backups of the cut: %+v", cut.Backups)
+	}
+	if seat.asks() != 1 {
+		t.Fatalf("the seat heard %d `now`", seat.asks())
+	}
+	// 3. The backup answers done: the walk's own step asks the first tier, once, and asks no second backup.
+	seat.answers("notes", true, "")
+	advancePlans(ctx, open)
+	advancePlans(ctx, open)
+	after, err := inv.PlanByID(ctx, ws[0].ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(*asked) != 1 || after.Backups.State != inventory.BackupDone || seat.asks() != 1 {
+		t.Fatalf("builds=%v backups=%+v asks=%d", *asked, after.Backups, seat.asks())
+	}
+}

cmd/mesh-controller/batches_integration_test.go

@@ -0,0 +1,698 @@
+//go:build integration
+
+package main
+
+import (
+	"bytes"
+	"io"
+	"os"
+	"slices"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+func windowed(t *testing.T) *stores {
+	t.Helper()
+	open := aMesh(t)
+	ctx := t.Context()
+	inv := open.inventory
+	settings := t.TempDir() + "/merge-window.json"
+	if err := os.WriteFile(settings, []byte(`{"merge-window": "90s", "merge-window-at-most": "10m"}`), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	t.Setenv(mergeWindowFileVar, settings)
+	noGroups(t)
+	if err := inv.RegisterModule(ctx, catalogue.Manifest{Module: "mesh-controller", Version: "1"},
+		inventory.Source{Repository: "novox/mesh-controller", Seat: "git", Ref: "main", BuiltFrom: "c0",
+			Head: "c0"}); err != nil {
+		t.Fatal(err)
+	}
+	for _, m := range []struct{ module, repository, path string }{
+		{"app", "novox/mesh-catalog", "modules/app"},
+		{"notes", "novox/mesh-catalog", "modules/notes"},
+		{"one", "novox/one", ""},
+		{"two", "novox/two", ""},
+		{"three", "novox/three", ""},
+	} {
+		if err := inv.RegisterModule(ctx, catalogue.Manifest{Module: m.module, Version: "1"},
+			inventory.Source{Repository: m.repository, Seat: "git", Path: m.path, Ref: "main", BuiltFrom: "c0",
+				Head: "c0"}); err != nil {
+			t.Fatal(err)
+		}
+	}
+	return open
+}
+
+func hear(t *testing.T, open *stores, m link.SourceMoved, now time.Time) {
+	t.Helper()
+	if err := (following{open: open}).hearMerge(t.Context(), m, now); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func cutAt(t *testing.T, open *stores, now time.Time) {
+	t.Helper()
+	if err := cutBatchesHeld(t.Context(), open, now); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestTwoMergesSecondsApartAreOneWalkAtTheLaterCommit(t *testing.T) {
+	open := windowed(t)
+	everyHeadWaits(t)
+	asked := asksWithPaths(t)
+	claude := catalogueMerge("553b7191claude", "app", t0)
+	dunst := catalogueMerge("48bda475dunst", "notes", t0.Add(17*time.Second))
+	hear(t, open, claude, t0.Add(time.Second))
+	hear(t, open, dunst, t0.Add(18*time.Second))
+	if ws, bs := walks(t, open); len(ws) != 0 || len(bs) != 1 {
+		t.Fatalf("within the window: %d walk(s), %d batch(es)", len(ws), len(bs))
+	}
+	cutAt(t, open, t0.Add(18*time.Second+89*time.Second))
+	if ws, _ := walks(t, open); len(ws) != 0 {
+		t.Fatalf("cut before the window closed: %+v", ws)
+	}
+	cutAt(t, open, t0.Add(18*time.Second+90*time.Second))
+	ws, bs := walks(t, open)
+	if len(ws) != 1 || len(bs) != 0 {
+		t.Fatalf("after the window: %d walk(s), %d batch(es)", len(ws), len(bs))
+	}
+	w := ws[0]
+	if w.Commit != dunst.Commit || len(w.Commits) != 1 || w.Commits[0].Commit != dunst.Commit {
+		t.Fatalf("the walk is at %s %+v, not the later commit", w.Commit, w.Commits)
+	}
+	for _, m := range []string{"app", "notes"} {
+		if _, in := w.Modules[m]; !in {
+			t.Fatalf("the walk does not build %s, which one of its merges moved: %v", m, w.Modules)
+		}
+	}
+	want := []inventory.PlanMerge{{Repository: "novox/mesh-catalog", Commit: claude.Commit, Carried: dunst.Commit},
+		{Repository: "novox/mesh-catalog", Commit: dunst.Commit}}
+	if w.Delivery == nil || !slices.EqualFunc(w.Delivery.Merges, want, sameMerge) {
+		t.Fatalf("the walk answers %+v, want %+v", w.Delivery, want)
+	}
+	if len(*asked) != 2 || (*asked)[0][2] != "main" || (*asked)[1][2] != "main" {
+		t.Fatalf("the walk did not ask its modules at the branch, which holds the commit it carries: %v", *asked)
+	}
+	// Heard again, as the bus may hand it over twice: never a second merge, nor a second walk.
+	hear(t, open, claude, t0.Add(5*time.Minute))
+	if ws, bs := walks(t, open); len(ws) != 1 || len(bs) != 0 {
+		t.Fatalf("a merge heard twice made %d walk(s) and %d batch(es)", len(ws), len(bs))
+	}
+}
+
+func TestThreeRepositoriesInOneWindowAreOneWalk(t *testing.T) {
+	open := windowed(t)
+	groupsWaiting(t, "feat/three")
+	asksRecorded(t)
+	for i, r := range []string{"one", "two", "three"} {
+		hear(t, open, fromHead(repoMerge(r, "c-"+r, t0.Add(time.Duration(i)*20*time.Second)), "feat/three"),
+			t0.Add(time.Duration(i)*20*time.Second+time.Second))
+	}
+	cutAt(t, open, t0.Add(41*time.Second+90*time.Second))
+	ws, bs := walks(t, open)
+	if len(ws) != 1 || len(bs) != 0 {
+		t.Fatalf("%d walk(s), %d batch(es)", len(ws), len(bs))
+	}
+	w := ws[0]
+	if len(w.Commits) != 3 || len(w.Delivery.Merges) != 3 {
+		t.Fatalf("the walk carries %+v and answers %+v", w.Commits, w.Delivery.Merges)
+	}
+	for _, r := range []string{"one", "two", "three"} {
+		if w.CommitOf("novox/"+r) != "c-"+r {
+			t.Fatalf("the walk carries %s at %q", r, w.CommitOf("novox/"+r))
+		}
+		if _, in := w.Modules[r]; !in {
+			t.Fatalf("the walk does not build %s: %v", r, w.Modules)
+		}
+	}
+	// Each module's ask is recorded at its own repository's commit.
+	for _, r := range []string{"one", "two", "three"} {
+		q, found, err := open.inventory.BuildRequestByID(t.Context(), w.Modules[r].Build)
+		if err != nil || !found || q.Commit != "c-"+r {
+			t.Fatalf("%s's build was not recorded at its own commit: %+v %v %v", r, q, found, err)
+		}
+	}
+}
+
+func TestAMergeRestartsTheWindowAndTheMaximumClosesIt(t *testing.T) {
+	open := windowed(t)
+	groupsWaiting(t, "feat/both", "feat/busy")
+	asksWithPaths(t)
+	hear(t, open, fromHead(repoMerge("one", "c1", t0), "feat/both"), t0)
+	hear(t, open, fromHead(repoMerge("two", "c2", t0.Add(80*time.Second)), "feat/both"), t0.Add(80*time.Second))
+	cutAt(t, open, t0.Add(100*time.Second))
+	if ws, _ := walks(t, open); len(ws) != 0 {
+		t.Fatal("the window closed 90 seconds after its first merge, not after its last")
+	}
+	cutAt(t, open, t0.Add(170*time.Second))
+	if ws, _ := walks(t, open); len(ws) != 1 || len(ws[0].Commits) != 2 {
+		t.Fatalf("the window did not close 90 seconds after its last merge: %+v", ws)
+	}
+
+	busy := windowed(t)
+	groupsWaiting(t, "feat/both", "feat/busy")
+	asksWithPaths(t)
+	var last time.Time
+	for i := 0; i < 12; i++ {
+		last = t0.Add(time.Duration(i) * time.Minute)
+		repo := []string{"one", "two", "three"}[i%3]
+		hear(t, busy, fromHead(repoMerge(repo, "c"+string(rune('a'+i)), last), "feat/busy"), last)
+		if ws, _ := walks(t, busy); len(ws) > 0 {
+			if i != 10 {
+				t.Fatalf("a busy window closed at merge %d (minute %d), not at its maximum", i, i)
+			}
+			break
+		}
+	}
+	ws, _ := walks(t, busy)
+	if len(ws) != 1 {
+		t.Fatalf("ten minutes of merges a minute apart were never cut: %d walk(s)", len(ws))
+	}
+}
+
+func TestTheAssemblingBatchIsShown(t *testing.T) {
+	open := windowed(t)
+	groupsWaiting(t, "pr/553b7191claude")
+	asksWithPaths(t)
+	var said []inventory.Plan
+	was := inventory.PlanSaved
+	inventory.PlanSaved = func(_ *inventory.Inventory, p inventory.Plan) { said = append(said, p) }
+	t.Cleanup(func() { inventory.PlanSaved = was })
+	now := time.Now().UTC()
+	claude := catalogueMerge("553b7191claude", "app", now.Add(-20*time.Second))
+	claude.Number, claude.Title = 174, "claude-code: an agent proposes a section"
+	dunst := catalogueMerge("48bda475dunst", "notes", now.Add(-2*time.Second))
+	dunst.Number, dunst.Title = 175, "dunst: the font the operator chose"
+	hear(t, open, claude, now.Add(-19*time.Second))
+	hear(t, open, dunst, now.Add(-time.Second))
+	hear(t, open, fromHead(repoMerge("one", "a6bc0931one", now), dunst.Head), now)
+	out := captured(t, func() error { return plansCommand(t.Context(), nil) })
+	lines := strings.Split(out, "\n")
+	first := lines[0]
+	for _, want := range []string{"assembling: ", " s left (at the latest ", "grouped: novox/mesh-catalog@48bda475 " +
+		"(answers 553b7191), novox/one@a6bc0931; plan not yet calculated"} {
+		if !strings.Contains(first, want) {
+			t.Fatalf("plans' first line %q does not say %q", first, want)
+		}
+	}
+	// Under it, one line per repository: the pull request, what it answers, what it moves.
+	if len(lines) < 3 || strings.TrimSpace(lines[1]) != "mesh-catalog #175 dunst: the font the operator chose (answers "+
+		"#174 claude-code: an agent proposes a section) · app, notes" ||
+		strings.TrimSpace(lines[2]) != "one a6bc0931 · one" {
+		t.Fatalf("the grouped list reads %q", lines[1:4])
+	}
+	if len(said) == 0 || said[len(said)-1].State != inventory.PlanAssembling || said[len(said)-1].Delivery.Batch == nil ||
+		len(said[len(said)-1].Delivery.Merges) != 3 {
+		t.Fatalf("the batch was not said as assembling with its merges: %+v", said)
+	}
+}
+
+func captured(t *testing.T, run func() error) string {
+	t.Helper()
+	r, w, err := os.Pipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+	was := os.Stdout
+	os.Stdout = w
+	runErr := run()
+	os.Stdout = was
+	_ = w.Close()
+	var b bytes.Buffer
+	_, _ = io.Copy(&b, r)
+	if runErr != nil {
+		t.Fatal(runErr)
+	}
+	return b.String()
+}
+
+func TestAMergeDuringAWalkJoinsTheNextBatch(t *testing.T) {
+	open := windowed(t)
+	asksWithPaths(t)
+	hear(t, open, repoMerge("one", "c1", t0), t0)
+	cutAt(t, open, t0.Add(90*time.Second))
+	ws, _ := walks(t, open)
+	if len(ws) != 1 || !ws[0].Open() {
+		t.Fatalf("the first batch was not cut: %+v", ws)
+	}
+	first := ws[0]
+	hear(t, open, repoMerge("one", "c2", t0.Add(2*time.Minute)), t0.Add(2*time.Minute))
+	cutAt(t, open, t0.Add(5*time.Minute))
+	ws, bs := walks(t, open)
+	if len(ws) != 1 || len(bs) != 1 || bs[0].State != inventory.PlanQueued || bs[0].Delivery.Batch.Behind != first.ID {
+		t.Fatalf("the merge during the walk: %d walk(s), batches %+v", len(ws), bs)
+	}
+	if got, _ := open.inventory.PlanByID(t.Context(), first.ID); !got.Open() {
+		t.Fatalf("the started walk was %s by the next merge", got.State)
+	}
+	if !strings.HasPrefix(batchWords(bs[0], t0.Add(5*time.Minute)), "queued behind "+first.ID) {
+		t.Fatalf("a queued batch reads %q", batchWords(bs[0], t0.Add(5*time.Minute)))
+	}
+	first.State = inventory.PlanDone
+	if err := open.inventory.SavePlan(t.Context(), &first); err != nil {
+		t.Fatal(err)
+	}
+	cutAt(t, open, t0.Add(6*time.Minute))
+	ws, bs = walks(t, open)
+	if len(ws) != 2 || len(bs) != 0 || ws[0].Commit != "c2" {
+		t.Fatalf("the queued batch was not cut when the walk ended: %+v %+v", ws, bs)
+	}
+}
+
+func TestAWaitingWalkIsFoldedIntoTheNextBatch(t *testing.T) {
+	open := windowed(t)
+	asksWithPaths(t)
+	ctx := t.Context()
+	if err := open.inventory.RegisterModule(ctx, catalogue.Manifest{Module: "mesh-delivery", Version: "1",
+		Claims: []catalogue.Claim{{Name: catalogue.DeliverySeat, Scope: catalogue.ScopeMesh}}},
+		inventory.Source{Repository: "novox/mesh-catalog", Seat: "git", Path: "modules/mesh-delivery", Ref: "main",
+			BuiltFrom: "c0", Head: "c0"}); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := open.inventory.Assign(ctx, "anchor", "mesh-delivery"); err != nil {
+		t.Fatal(err)
+	}
+	hear(t, open, repoMerge("one", "c1", t0), t0)
+	cutAt(t, open, t0.Add(90*time.Second))
+	ws, _ := walks(t, open)
+	if len(ws) != 1 || !ws[0].Waiting() {
+		t.Fatalf("the walk does not wait for its word: %+v", ws)
+	}
+	waiting := ws[0]
+	hear(t, open, repoMerge("one", "c2", t0.Add(2*time.Minute)), t0.Add(2*time.Minute))
+	cutAt(t, open, t0.Add(2*time.Minute+90*time.Second))
+	ws, bs := walks(t, open)
+	if len(bs) != 0 || len(ws) != 2 {
+		t.Fatalf("%d walk(s), %d batch(es)", len(ws), len(bs))
+	}
+	folded, err := open.inventory.PlanByID(ctx, waiting.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	newer := ws[0]
+	if folded.State != inventory.PlanSuperseded || folded.Delivery.TakenOverBy != newer.ID {
+		t.Fatalf("the waiting walk is %s, taken over by %q", folded.State, folded.Delivery.TakenOverBy)
+	}
+	if len(newer.Delivery.Merges) != 2 || newer.CommitOf("novox/one") != "c2" {
+		t.Fatalf("the newer walk answers %+v", newer.Delivery.Merges)
+	}
+	if _, in := newer.Modules["one"]; !in {
+		t.Fatalf("what the folded walk was to build is not built: %v", newer.Modules)
+	}
+}
+
+func TestALateMergeIsAnsweredByTheWalkOfTheLaterOne(t *testing.T) {
+	open := windowed(t)
+	everyHeadWaits(t)
+	asksWithPaths(t)
+	ctx := t.Context()
+	later := catalogueMerge("48bda475dunst", "notes", t0.Add(17*time.Second))
+	hear(t, open, later, t0.Add(18*time.Second))
+	cutAt(t, open, t0.Add(2*time.Minute))
+	ws, _ := walks(t, open)
+	w := ws[0]
+	w.State = inventory.PlanDone
+	if err := open.inventory.SavePlan(ctx, &w); err != nil {
+		t.Fatal(err)
+	}
+	// Moves only notes, which the done walk built from the branch after it: answered there, at once.
+	hear(t, open, catalogueMerge("553b7191early", "notes", t0), t0.Add(15*time.Minute))
+	got, _ := open.inventory.PlanByID(ctx, w.ID)
+	if got.State != inventory.PlanDone || len(got.Delivery.Merges) != 2 ||
+		!sameMerge(got.Delivery.Merges[0], inventory.PlanMerge{Repository: "novox/mesh-catalog", Commit: "553b7191early",
+			Carried: later.Commit}) {
+		t.Fatalf("the late merge is not named by the walk that carried it: %+v", got.Delivery.Merges)
+	}
+	// Moves app, which that walk never built: the next batch walks it.
+	hear(t, open, catalogueMerge("1111aaaaapp", "app", t0.Add(time.Second)), t0.Add(16*time.Minute))
+	_, bs := walks(t, open)
+	if len(bs) != 1 || bs[0].Delivery.Merges[0].Commit != "1111aaaaapp" {
+		t.Fatalf("a late merge moving what the walk never built did not join the next batch: %+v", bs)
+	}
+}
+
+func TestAFailedWalkWalksItsEarlierMergesAlone(t *testing.T) {
+	open := windowed(t)
+	everyHeadWaits(t)
+	asked := asksWithPaths(t)
+	ctx := t.Context()
+	// Made before the cut marks their modules seen, as merges are: walked again, they are news all the same.
+	oldest := catalogueMerge("aaaa0001", "app", t0.Add(-3*time.Minute))
+	middle := catalogueMerge("bbbb0002", "app", t0.Add(-3*time.Minute+10*time.Second))
+	newest := catalogueMerge("cccc0003", "notes", t0.Add(-3*time.Minute+20*time.Second))
+	for i, m := range []link.SourceMoved{oldest, middle, newest} {
+		hear(t, open, m, t0.Add(time.Duration(i)*10*time.Second+time.Second))
+	}
+	cutAt(t, open, t0.Add(2*time.Minute))
+	ws, _ := walks(t, open)
+	failed := ws[0]
+	failed.State, failed.Note = inventory.PlanFailed, "notes failed to build in tier 0"
+	if err := open.inventory.SavePlan(ctx, &failed); err != nil {
+		t.Fatal(err)
+	}
+	cutAt(t, open, t0.Add(3*time.Minute))
+	got, _ := open.inventory.PlanByID(ctx, failed.ID)
+	if got.State != inventory.PlanFailed || len(got.Delivery.Merges) != 3 {
+		t.Fatalf("the failed walk's record changed: %s %+v", got.State, got.Delivery.Merges)
+	}
+	ws, _ = walks(t, open)
+	alone := ws[0]
+	if alone.ID == failed.ID || alone.Commit != middle.Commit || len(alone.Delivery.Merges) != 1 ||
+		!sameMerge(alone.Delivery.Merges[0], inventory.PlanMerge{Repository: "novox/mesh-catalog", Commit: middle.Commit}) {
+		t.Fatalf("the newest earlier merge was not walked alone on its own commit: %+v", alone)
+	}
+	if _, in := alone.Modules["app"]; !in || (*asked)[len(*asked)-1] != [3]string{"novox/mesh-catalog", "modules/app",
+		middle.Commit} {
+		t.Fatalf("the merge walked alone does not build app at its own commit: %v, asked %v", alone.Modules, *asked)
+	}
+	// Retried, the failed walk would name merges the search answers now.
+	if _, err := retryPlan(ctx, open, failed.ID); err == nil || !strings.Contains(err.Error(), "walked alone") {
+		t.Fatalf("a failed walk whose merges are searched was retried: %v", err)
+	}
+	alone.State = inventory.PlanDone
+	if err := open.inventory.SavePlan(ctx, &alone); err != nil {
+		t.Fatal(err)
+	}
+	cutAt(t, open, t0.Add(4*time.Minute))
+	ws, bs := walks(t, open)
+	if ws[0].ID != alone.ID || len(bs) != 0 {
+		t.Fatalf("the search went on after a merge was delivered: %+v", ws[0])
+	}
+	done, _ := open.inventory.PlanByID(ctx, alone.ID)
+	if len(done.Delivery.Merges) != 2 || !sameMerge(done.Delivery.Merges[0], inventory.PlanMerge{Repository: "novox/mesh-catalog",
+		Commit: oldest.Commit, Carried: middle.Commit}) {
+		t.Fatalf("the oldest merge is not answered by the walk that delivered the one after it: %+v", done.Delivery.Merges)
+	}
+	// A stopped walk starts no search: a person ended it.
+	hear(t, open, catalogueMerge("dddd0004", "app", t0.Add(5*time.Minute)), t0.Add(5*time.Minute))
+	hear(t, open, catalogueMerge("eeee0005", "notes", t0.Add(5*time.Minute+time.Second)), t0.Add(5*time.Minute+time.Second))
+	cutAt(t, open, t0.Add(8*time.Minute))
+	ws, _ = walks(t, open)
+	if _, err := stopWalk(ctx, open.inventory, ws[0].ID, "mesh-delivery for jochen", "not now"); err != nil {
+		t.Fatal(err)
+	}
+	cutAt(t, open, t0.Add(9*time.Minute))
+	if again, _ := walks(t, open); again[0].ID != ws[0].ID {
+		t.Fatalf("a stopped walk's earlier merge was walked alone: %+v", again[0])
+	}
+}
+
+func TestAGroupsOrderBecomesTiersInsideTheWalk(t *testing.T) {
+	for _, grouped := range []bool{true, false} {
+		open := windowed(t)
+		everyHeadWaits(t)
+		asksWithPaths(t)
+		ctx := t.Context()
+		for _, m := range []string{"mesh-host"} {
+			if err := open.inventory.RegisterModule(ctx, catalogue.Manifest{Module: m, Version: "1"},
+				inventory.Source{Repository: "novox/" + m, Seat: "git", Ref: "main", BuiltFrom: "c0", Head: "c0"}); err != nil {
+				t.Fatal(err)
+			}
+		}
+		host := repoMerge("mesh-host", "h1", t0)
+		ctl := repoMerge("mesh-controller", "k1", t0.Add(time.Second))
+		host.Head, ctl.Head = "feat/together", "feat/together"
+		if !grouped {
+			ctl.Head = "feat/alone"
+		}
+		hear(t, open, ctl, t0.Add(2*time.Second))
+		hear(t, open, host, t0.Add(3*time.Second))
+		cutAt(t, open, t0.Add(2*time.Minute))
+		ws, _ := walks(t, open)
+		if len(ws) != 1 {
+			t.Fatalf("%d walks", len(ws))
+		}
+		tiers := ws[0].Tiers
+		if grouped {
+			if len(tiers) != 2 || !slices.Equal(tiers[0], []string{"mesh-host"}) ||
+				!slices.Equal(tiers[1], []string{"mesh-controller"}) {
+				t.Fatalf("the group's order is not the walk's tiers: %v", tiers)
+			}
+		} else if len(tiers) != 1 {
+			t.Fatalf("two merges of no group were ordered: %v", tiers)
+		}
+	}
+}
+
+func TestABatchSurvivesARestart(t *testing.T) {
+	open := windowed(t)
+	groupsWaiting(t, "feat/both")
+	asksWithPaths(t)
+	hear(t, open, fromHead(repoMerge("one", "c1", t0), "feat/both"), t0)
+	hear(t, open, fromHead(repoMerge("two", "c2", t0.Add(30*time.Second)), "feat/both"), t0.Add(30*time.Second))
+
+	// A new controller: nothing of the first one's but the store.
+	again, err := openStores(t.Context())
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(again.Close)
+	hear(t, again, fromHead(repoMerge("one", "c1", t0), "feat/both"), t0.Add(60*time.Second)) // the bus hands it over again
+	cutAt(t, again, t0.Add(119*time.Second))
+	if ws, bs := walks(t, again); len(ws) != 0 || len(bs) != 1 || len(bs[0].Delivery.Merges) != 2 {
+		t.Fatalf("the restarted controller's batch: %d walk(s), %+v", len(ws), bs)
+	}
+	cutAt(t, again, t0.Add(120*time.Second))
+	ws, bs := walks(t, again)
+	if len(ws) != 1 || len(bs) != 0 || len(ws[0].Delivery.Merges) != 2 {
+		t.Fatalf("the restarted controller did not cut the batch at its window: %+v %+v", ws, bs)
+	}
+}
+
+func TestALateMergeOfAOneModuleRepositoryIsNamed(t *testing.T) {
+	open := windowed(t)
+	everyHeadWaits(t)
+	asksWithPaths(t)
+	ctx := t.Context()
+	c2 := repoMerge("one", "c2", t0.Add(-50*time.Second))
+	hear(t, open, c2, t0)
+	cutAt(t, open, t0.Add(2*time.Minute))
+	ws, _ := walks(t, open)
+	w := ws[0]
+	w.State = inventory.PlanDone
+	if err := open.inventory.SavePlan(ctx, &w); err != nil {
+		t.Fatal(err)
+	}
+	hear(t, open, repoMerge("one", "c1", t0.Add(-60*time.Second)), t0.Add(15*time.Minute))
+	got, _ := open.inventory.PlanByID(ctx, w.ID)
+	if len(got.Delivery.Merges) != 2 || !sameMerge(got.Delivery.Merges[0], inventory.PlanMerge{Repository: "novox/one",
+		Commit: "c1", Carried: "c2"}) {
+		t.Fatalf("the late merge was not named by the walk that carried it: %+v", got.Delivery.Merges)
+	}
+
+	// A walk of two that built only two: a late merge of one is not its to name.
+	hear(t, open, repoMerge("two", "d2", t0.Add(16*time.Minute)), t0.Add(16*time.Minute))
+	cutAt(t, open, t0.Add(18*time.Minute))
+	ws, _ = walks(t, open)
+	w = ws[0]
+	delete(w.Modules, "two")
+	w.State = inventory.PlanDone
+	if err := open.inventory.SavePlan(ctx, &w); err != nil {
+		t.Fatal(err)
+	}
+	hear(t, open, repoMerge("two", "d1", t0.Add(15*time.Minute)), t0.Add(20*time.Minute))
+	if got, _ := open.inventory.PlanByID(ctx, w.ID); len(got.Delivery.Merges) != 1 {
+		t.Fatalf("a walk that never built what the late merge moves named it: %+v", got.Delivery.Merges)
+	}
+	if _, bs := walks(t, open); len(bs) != 1 || bs[0].Delivery.Merges[0].Commit != "d1" {
+		t.Fatalf("the late merge did not join the next batch: %+v", bs)
+	}
+}
+
+func TestAWalkLetGoBesideAStartedOneStartsOnceItEnded(t *testing.T) {
+	open := windowed(t)
+	asked := asksWithPaths(t)
+	ctx := t.Context()
+	hear(t, open, repoMerge("one", "c1", t0), t0)
+	cutAt(t, open, t0.Add(2*time.Minute))
+	started, _ := walks(t, open)
+	waiting := inventory.Plan{ID: "plan-waiting", Repository: "novox/one", Branch: "main", Commit: "d1", Created: t0,
+		State: inventory.PlanBuilding, Tiers: [][]string{{"one"}}, Modules: map[string]*inventory.PlanModule{"one": {}},
+		Delivery: &inventory.PlanDelivery{Awaits: catalogue.DeliverySeat}}
+	if err := open.inventory.SavePlan(ctx, &waiting); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := letGo(ctx, open.inventory, waiting.ID, catalogue.DeliverySeat, "its turn"); err != nil {
+		t.Fatalf("the word was refused beside %s: %v", started[0].ID, err)
+	}
+	before := len(*asked)
+	advanceHeld(ctx, open)
+	got, _ := open.inventory.PlanByID(ctx, waiting.ID)
+	if len(*asked) != before || !strings.Contains(got.Note, "starts once "+started[0].ID) {
+		t.Fatalf("a walk let go beside a started one asked (%d → %d) or does not say it waits: %q", before, len(*asked), got.Note)
+	}
+	// Read as a wait, an hour on: its note on the line, never LATE, and no tier of it late for S3.
+	later := time.Now().Add(time.Hour)
+	if line := planLine(got, later); !strings.Contains(line, "starts once "+started[0].ID) || strings.Contains(line, "LATE") {
+		t.Fatalf("a deferred walk reads %q", line)
+	}
+	facts, _, err := gatherPlans(ctx, open.inventory, later, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, f := range facts {
+		if f.id == got.ID {
+			t.Fatalf("a deferred walk is watched as a tier running late: %+v", f)
+		}
+	}
+	done := started[0]
+	done.State = inventory.PlanDone
+	if err := open.inventory.SavePlan(ctx, &done); err != nil {
+		t.Fatal(err)
+	}
+	advanceHeld(ctx, open)
+	if len(*asked) != before+1 {
+		t.Fatalf("the walk did not start once the started one ended: asked %v", *asked)
+	}
+}
+
+func TestAMergeOnTheControllersPathNeverSharesABatch(t *testing.T) {
+	open := windowed(t)
+	everyHeadWaits(t)
+	asked := asksWithPaths(t)
+	ctx := t.Context()
+	if err := open.inventory.RegisterModule(ctx, catalogue.Manifest{Module: "mesh-delivery", Version: "1",
+		Claims: []catalogue.Claim{{Name: catalogue.DeliverySeat, Scope: catalogue.ScopeMesh}}},
+		inventory.Source{Repository: "novox/mesh-catalog", Seat: "git", Path: "modules/mesh-delivery", Ref: "main",
+			BuiltFrom: "c0", Head: "c0"}); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := open.inventory.Assign(ctx, "anchor", "mesh-delivery"); err != nil {
+		t.Fatal(err)
+	}
+	hear(t, open, catalogueMerge("aaaa0001", "app", t0), t0)
+	hear(t, open, repoMerge("mesh-controller", "k1", t0.Add(10*time.Second)), t0.Add(10*time.Second))
+	hear(t, open, catalogueMerge("bbbb0002", "notes", t0.Add(20*time.Second)), t0.Add(20*time.Second))
+	_, bs := walks(t, open)
+	var ownBatch, catalogueBatch inventory.Plan
+	for _, b := range bs {
+		if b.OwnPath() {
+			ownBatch = b
+		} else {
+			catalogueBatch = b
+		}
+	}
+	if len(bs) != 2 || ownBatch.ID == "" || catalogueBatch.ID == "" || len(catalogueBatch.Delivery.Merges) != 2 ||
+		len(ownBatch.Delivery.Merges) != 1 {
+		t.Fatalf("a controller merge and two catalogue merges in one window: %+v", bs)
+	}
+	if !strings.Contains(batchWords(ownBatch, t0.Add(30*time.Second)), "own path") {
+		t.Fatalf("the own-path batch does not say so: %q", batchWords(ownBatch, t0.Add(30*time.Second)))
+	}
+	// Both windows closed, the controller's batch is cut first and starts; the catalogue batch queues behind it,
+	// is cut when the controller's walk ended, and waits for its word with both merges.
+	cutAt(t, open, t0.Add(2*time.Minute))
+	ws, bs := walks(t, open)
+	if len(ws) != 1 || ws[0].Waiting() || ws[0].CommitOf("novox/mesh-controller") != "k1" {
+		t.Fatalf("the controller's batch was not cut first into a started walk: %+v", ws)
+	}
+	ownWalk := ws[0]
+	for _, m := range []string{"app", "notes"} {
+		if _, in := ownWalk.Modules[m]; in {
+			t.Fatalf("the controller's walk builds %s, a catalogue module: it skipped its turn", m)
+		}
+	}
+	if len(bs) != 1 || bs[0].State != inventory.PlanQueued || bs[0].Delivery.Batch.Behind != ownWalk.ID || bs[0].OwnPath() {
+		t.Fatalf("the catalogue batch does not queue behind the controller's walk: %+v", bs)
+	}
+	ownWalk.State = inventory.PlanDone
+	if err := open.inventory.SavePlan(ctx, &ownWalk); err != nil {
+		t.Fatal(err)
+	}
+	cutAt(t, open, t0.Add(3*time.Minute))
+	ws, bs = walks(t, open)
+	if len(bs) != 0 || ws[0].ID != catalogueBatch.ID || !ws[0].Waiting() || len(ws[0].Delivery.Merges) != 2 {
+		t.Fatalf("the catalogue batch was not cut into a waiting walk once the controller's ended: %+v %+v", ws, bs)
+	}
+	for _, m := range []string{"app", "notes"} {
+		if _, in := ws[0].Modules[m]; !in {
+			t.Fatalf("the catalogue walk does not build %s: %v", m, ws[0].Modules)
+		}
+	}
+	for _, a := range *asked {
+		if a[1] == "modules/app" || a[1] == "modules/notes" {
+			t.Fatalf("a catalogue module was asked without the word: %v", *asked)
+		}
+	}
+
+	// A catalogue walk waiting for its word when an own-path batch is cut keeps waiting beside the own-path
+	// walk, is not folded into it, and its word is taken meanwhile: it starts once the own-path walk ended.
+	catalogueWalk := ws[0]
+	hear(t, open, repoMerge("mesh-controller", "k2", t0.Add(4*time.Minute)), t0.Add(4*time.Minute))
+	cutAt(t, open, t0.Add(6*time.Minute))
+	ws, _ = walks(t, open)
+	kept, _ := open.inventory.PlanByID(ctx, catalogueWalk.ID)
+	if !kept.Waiting() || ws[0].CommitOf("novox/mesh-controller") != "k2" || ws[0].Waiting() {
+		t.Fatalf("the waiting catalogue walk was not kept waiting beside the controller's walk: %s %+v", kept.State, ws)
+	}
+	if _, in := ws[0].Modules["app"]; in {
+		t.Fatalf("the controller's walk folded the waiting catalogue walk in: %v", ws[0].Modules)
+	}
+	if _, err := letGo(ctx, open.inventory, catalogueWalk.ID, catalogue.DeliverySeat, "its turn"); err != nil {
+		t.Fatal(err)
+	}
+	before := len(*asked)
+	advanceHeld(ctx, open)
+	if len(*asked) != before {
+		t.Fatalf("the catalogue walk started beside the controller's: asked %v", (*asked)[before:])
+	}
+	own2 := ws[0]
+	own2.State = inventory.PlanDone
+	if err := open.inventory.SavePlan(ctx, &own2); err != nil {
+		t.Fatal(err)
+	}
+	advanceHeld(ctx, open)
+	if len(*asked) < before+1 || (*asked)[before][1] != "modules/app" {
+		t.Fatalf("the catalogue walk did not start once the controller's ended: %v", (*asked)[before:])
+	}
+}
+
+func TestALateCatalogueMergeIsNotAnsweredByAnOwnPathWalk(t *testing.T) {
+	open := windowed(t)
+	everyHeadWaits(t)
+	asksWithPaths(t)
+	ctx := t.Context()
+	for _, m := range []struct {
+		module string
+		claims []catalogue.Claim
+	}{
+		{"nats", nil},
+		{"mesh-delivery", []catalogue.Claim{{Name: catalogue.DeliverySeat, Scope: catalogue.ScopeMesh}}},
+	} {
+		if err := open.inventory.RegisterModule(ctx, catalogue.Manifest{Module: m.module, Version: "1", Claims: m.claims},
+			inventory.Source{Repository: "novox/mesh-catalog", Seat: "git", Path: "modules/" + m.module, Ref: "main",
+				BuiltFrom: "c0", Head: "c0"}); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if _, err := open.inventory.Assign(ctx, "anchor", "mesh-delivery"); err != nil {
+		t.Fatal(err)
+	}
+	mixed := link.SourceMoved{Owner: "novox", Repo: "mesh-catalog", Base: "main", Commit: "m1xed", MergedAt: t0.Format(time.RFC3339Nano),
+		Paths: []string{"modules/nats/module.json", "modules/app/module.json"}, ModuleDirs: []string{"modules/nats", "modules/app"},
+		ModuleDirsSaid: true}
+	hear(t, open, mixed, t0.Add(time.Second))
+	cutAt(t, open, t0.Add(2*time.Minute))
+	ws, _ := walks(t, open)
+	if len(ws) != 1 || ws[0].Waiting() {
+		t.Fatalf("the mixed merge's walk waited, or was not cut: %+v", ws)
+	}
+	done := ws[0]
+	done.State = inventory.PlanDone
+	if err := open.inventory.SavePlan(ctx, &done); err != nil {
+		t.Fatal(err)
+	}
+	hear(t, open, catalogueMerge("ear1ier", "app", t0.Add(-30*time.Second)), t0.Add(3*time.Minute))
+	got, _ := open.inventory.PlanByID(ctx, done.ID)
+	_, bs := walks(t, open)
+	if len(got.Delivery.Merges) != 1 || len(bs) != 1 || bs[0].OwnPath() || bs[0].Delivery.Merges[0].Commit != "ear1ier" {
+		t.Fatalf("the late catalogue merge was answered by the own-path walk (%+v) rather than the next catalogue batch (%+v)",
+			got.Delivery.Merges, bs)
+	}
+}

cmd/mesh-controller/batches_test.go

@@ -0,0 +1,293 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"os"
+	"slices"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// The suite's tests of a merge, but for the merge window's own (this file's), plan the merge as it is heard: a
+// window of nothing closes at once, so a merge with no walk open is cut into its walk at once, as every merge
+// was planned before novox/hq ADR 0276. The window's tests set it through the controller's settings.
+func init() {
+	mergeWindowDefault = 0
+	// No forge in a test: no manifest is found at any commit, so a merge draws no edge of the manifests' change
+	// (delivery_edges.go). A test that wants some replaces these (forgeHolding).
+	manifestAt = func(context.Context, string, string, string, string) (catalogue.Manifest, bool, error) {
+		return catalogue.Manifest{}, false, nil
+	}
+	parentOf = func(context.Context, string, string, string) (string, error) { return "", nil }
+}
+
+// windowed is a mesh whose controller's settings give a merge window of 90 seconds and at most 10 minutes, as its
+// settings file says them, and
+// modules built from the catalogue (app, notes) and from three repositories of their own.
+
+// t0 is the moment a test's clock starts: merges are dated by it, and heard after it.
+var t0 = time.Now().UTC().Truncate(time.Second)
+
+// catalogueMerge is a merge of the catalogue changing one module's directory, made at a moment, from a pull
+// request's head branch of its own, as the forge announces every merge. Whether its head names a delivery group
+// with a member still to merge is mesh-delivery's word, which windowed stubs as no group at all (noGroups); a test
+// whose merges wait for the window as a group's says so (groupsWaiting).
+func catalogueMerge(commit, module string, made time.Time) link.SourceMoved {
+	return link.SourceMoved{Owner: "novox", Repo: "mesh-catalog", Base: "main", Head: "pr/" + commit, Commit: commit,
+		MergedAt: made.Format(time.RFC3339Nano), Paths: []string{"modules/" + module + "/module.json"},
+		ModuleDirs: []string{"modules/" + module}, ModuleDirsSaid: true}
+}
+
+// repoMerge is a merge of a repository of one module's own, from a head branch of its own (catalogueMerge).
+func repoMerge(repo, commit string, made time.Time) link.SourceMoved {
+	return link.SourceMoved{Owner: "novox", Repo: repo, Base: "main", Head: "pr/" + commit, Commit: commit,
+		MergedAt: made.Format(time.RFC3339Nano), Paths: []string{"main.go"}}
+}
+
+// noGroups stubs mesh-delivery's word on groups for a test: no head names a group.
+func noGroups(t *testing.T) {
+	t.Helper()
+	was := deliveryGroupOf
+	deliveryGroupOf = func(context.Context, bool, string) ([]groupMember, bool, error) { return nil, false, nil }
+	t.Cleanup(func() { deliveryGroupOf = was })
+}
+
+// groupsWaiting stubs mesh-delivery's word on groups for a test of the merge window's own timing: each head named
+// is one whose group mesh-delivery cannot say, so a merge from it waits for the window (ADR 0306 decision 2) and
+// nothing holds the batch open; every other head names no group. A group with a member still to merge, which holds
+// its batch open however long it takes (ADR 0418 clause 3), is groupStates'.
+func groupsWaiting(t *testing.T, heads ...string) {
+	t.Helper()
+	was := deliveryGroupOf
+	deliveryGroupOf = func(_ context.Context, _ bool, head string) ([]groupMember, bool, error) {
+		if slices.Contains(heads, head) {
+			return nil, false, errors.New("the test's mesh-delivery does not say")
+		}
+		return nil, false, nil
+	}
+	t.Cleanup(func() { deliveryGroupOf = was })
+}
+
+// everyHeadWaits stubs mesh-delivery's word on groups for a test whose merges each wait for the window as they did
+// before novox/hq ADR 0304: mesh-delivery cannot say any head's group.
+func everyHeadWaits(t *testing.T) {
+	t.Helper()
+	was := deliveryGroupOf
+	deliveryGroupOf = func(context.Context, bool, string) ([]groupMember, bool, error) {
+		return nil, false, errors.New("the test's mesh-delivery does not say")
+	}
+	t.Cleanup(func() { deliveryGroupOf = was })
+}
+
+// groupStates stubs mesh-delivery's word on one group: its members and their states, which a test changes as the
+// members merge.
+func groupStates(t *testing.T, head string, states map[string]string) {
+	t.Helper()
+	groupStatesFrom(t, head, states, true)
+}
+
+// groupStatesFrom is groupStates for a mesh-delivery that does (composed) or does not yet say the group's gate is the
+// composed check's: only the first holds the group's batch open for its last member.
+func groupStatesFrom(t *testing.T, head string, states map[string]string, composed bool) {
+	t.Helper()
+	was := deliveryGroupOf
+	deliveryGroupOf = func(_ context.Context, _ bool, asked string) ([]groupMember, bool, error) {
+		if asked != head {
+			return nil, false, nil
+		}
+		var members []groupMember
+		for repository, state := range states {
+			members = append(members, groupMember{Repository: repository, State: state, Composed: composed})
+		}
+		return members, true, nil
+	}
+	t.Cleanup(func() { deliveryGroupOf = was })
+}
+
+// fromHead is a merge from a head branch a test names: merges from one head are members of one delivery group,
+// related by it (novox/hq ADR 0304 decision 1), so they share a batch whatever else they share.
+func fromHead(m link.SourceMoved, head string) link.SourceMoved {
+	m.Head = head
+	return m
+}
+
+// lone is a merge that names no head: known to be no delivery group's, it waits for no window unless it is
+// related to a batch assembling (ADR 0304 decision 1).
+func lone(m link.SourceMoved) link.SourceMoved {
+	m.Head = ""
+	return m
+}
+
+// hear is a merge heard at a moment.
+
+// cutAt is the cutter looking at a moment.
+
+// walks is every plan record that is a walk, newest first, and the batches not yet cut.
+func walks(t *testing.T, open *stores) (walks, batches []inventory.Plan) {
+	t.Helper()
+	recent, err := open.inventory.RecentPlans(t.Context(), 50)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, p := range recent {
+		if p.Batch() {
+			batches = append(batches, p)
+		} else {
+			walks = append(walks, p)
+		}
+	}
+	return walks, batches
+}
+
+// The replay of issue 362: two catalogue merges 18 seconds apart are one batch, cut once into one walk at the
+// later commit, which names both merges — the earlier carried by the later.
+
+// Merges of three repositories in one window are one walk, one commit for each.
+
+// Each merge restarts the window: a merge at second 80 keeps the batch open until second 170; the window
+// closes at most ten minutes after its first merge however busy.
+
+// `plans` lists the batch being assembled first, in the operator's words: how long is left, when at the latest,
+// what is grouped, and that the plan is not yet calculated. It says so on the bus as plan-moved, too.
+
+// captured is what a command printed.
+
+// A merge heard during a walk it is related to (the same repository, issue 973) joins the next batch, which is
+// cut when the walk ends; the walk that started is never superseded (ADR 0276 decision 4, ADR 0407 decision 4).
+
+// A walk waiting for its delivery's word is folded into the next batch's walk, which answers its merges; it
+// names the walk that took it over.
+
+// A merge heard after a later merge of its branch was walked is answered by that walk when it builds all it
+// moves — named at once on a walk done — and joins the next batch when it does not.
+
+// A failed walk marks nothing delivered: its earlier merges are walked alone, on their own commit, the newest
+// first; the first delivered answers the older ones, and the search stops.
+
+// A delivery group's order holds inside the walk (ADR 0249 unchanged): merges of two repositories from one head
+// branch name, the node-engine's before the controller's, are tiered so; without the group, one tier.
+
+// A restarted controller resumes the window where it stood: the batch, its merges and their times are in the
+// store, a merge handed over again is not doubled, and the batch is cut when its window closes.
+
+// The window's settings reach the controller in its settings file, read at every look; one that says no
+// duration, or no file, is the default.
+func TestTheWindowIsTheControllersSetting(t *testing.T) {
+	file := t.TempDir() + "/merge-window.json"
+	t.Setenv(mergeWindowFileVar, file)
+	for _, c := range []struct {
+		content        string
+		window, atMost time.Duration
+	}{
+		{`{"merge-window": "60s", "merge-window-at-most": "5m"}`, time.Minute, 5 * time.Minute},
+		{`{"merge-window": 30, "merge-window-at-most": ""}`, 30 * time.Second, mergeWindowAtMostDefault},
+		{`{"merge-window": "soon"}`, mergeWindowDefault, mergeWindowAtMostDefault},
+	} {
+		if err := os.WriteFile(file, []byte(c.content), 0o600); err != nil {
+			t.Fatal(err)
+		}
+		if w, m := mergeWindowOf(); w != c.window || m != c.atMost {
+			t.Errorf("%s reads as %s and %s, want %s and %s", c.content, w, m, c.window, c.atMost)
+		}
+	}
+	t.Setenv(mergeWindowFileVar, file+".gone")
+	if w, m := mergeWindowOf(); w != mergeWindowDefault || m != mergeWindowAtMostDefault {
+		t.Errorf("no file reads as %s and %s", w, m)
+	}
+}
+
+// S16 names every merge a waiting walk answers, never one commit a supersession may have ended (issue 362).
+func TestAWaitingWalkNamesTheMergesItAnswers(t *testing.T) {
+	f := calm(t0)
+	f.waits = []waitFacts{{id: "plan-2", repository: "novox/mesh-catalog", commit: "48bda475dunst", awaits: "mesh-delivery",
+		since: t0.Add(-31 * time.Minute), merges: []inventory.PlanMerge{
+			{Repository: "novox/mesh-catalog", Commit: "553b7191claude", Carried: "48bda475dunst"},
+			{Repository: "novox/mesh-catalog", Commit: "48bda475dunst"}}}}
+	got := watchWaits(f)
+	if len(got) != 1 || !strings.Contains(got[0].Summary, "novox/mesh-catalog@553b7191") ||
+		!strings.Contains(got[0].Summary, "novox/mesh-catalog@48bda475") {
+		t.Fatalf("the waiting walk does not name both merges: %+v", got)
+	}
+}
+
+// A merge heard after a later merge of its branch was cut is named by that walk however its modules read since
+// the cut, in a repository of one module (review of this change); a walk that never built what it moves names
+// nothing, and the merge joins the next batch.
+
+// A related walk waits for the delivery's word too: a waiting walk let go beside a started one it is related to
+// (the same repository, issue 973) takes the word and starts once that one ended, asking nothing before.
+
+// A file a merge of the batch removed and a later one brought back is not removed; one removed last is.
+func TestARemovedFileIsTheLastMergesWord(t *testing.T) {
+	ev := func(commit string, paths, removed []string) inventory.BatchedMerge {
+		m := link.SourceMoved{Owner: "novox", Repo: "one", Base: "main", Commit: commit, Paths: paths, Removed: removed}
+		b, _ := json.Marshal(m)
+		return inventory.BatchedMerge{Repository: "novox/one", Branch: "main", Commit: commit, Event: b,
+			Merged: t0.Add(time.Duration(len(commit)) * time.Second)}
+	}
+	got := combinedMerges([]inventory.BatchedMerge{
+		ev("a", []string{"x/module.json", "y/module.json"}, []string{"x/module.json", "y/module.json"}),
+		ev("bb", []string{"x/module.json"}, nil),
+		ev("ccc", []string{"z.go"}, nil)})
+	if len(got) != 1 || got[0].Commit != "ccc" || !slices.Equal(got[0].Removed, []string{"y/module.json"}) ||
+		len(got[0].Paths) != 3 {
+		t.Fatalf("combined as %+v", got)
+	}
+}
+
+// A merge on the controller's own path never shares a batch with one that waits for mesh-delivery's word
+// (decided during the build, 2026-10-10): the two are batches of their own, cut one after the other; a walk on
+// the own path folds no waiting catalogue walk but batches its merges again behind it; the catalogue's walk
+// still waits for the word, so no catalogue delivery skips its turn.
+
+// `plans` names a walk by what it moves (asked by the operator, 2026-10-10): the repository's pull request and
+// title, the modules it moves and the machines running them, then the state words; a record naming no pull
+// request is named by its commit, and a title is cut at fifty runes.
+func TestAPlanLineNamesWhatItMoves(t *testing.T) {
+	now := time.Date(2026, 10, 10, 12, 0, 0, 0, time.UTC)
+	p := inventory.Plan{ID: "plan-1", Repository: "novox/mesh-catalog", Branch: "main", Commit: "c1c1c1c1c1",
+		State: inventory.PlanBuilding, Tiers: [][]string{{"messenger", "telegram"}}, TierEntered: now.Add(-2 * time.Minute),
+		Modules: map[string]*inventory.PlanModule{"messenger": {State: "asked"}, "telegram": {State: "asked"}},
+		Commits: []inventory.PlanCommit{{Repository: "novox/mesh-catalog", Branch: "main", Commit: "c1c1c1c1c1"}},
+		Delivery: &inventory.PlanDelivery{Merges: []inventory.PlanMerge{{Repository: "novox/mesh-catalog",
+			Commit: "c1c1c1c1c1", Number: 175, Title: "a tap shows its outcome", Moves: []string{"telegram", "messenger"}}}}}
+	running := func(module string) []string {
+		if module == "messenger" || module == "telegram" {
+			return []string{"novox"}
+		}
+		return nil
+	}
+	if got, want := planLineOn(p, now, pauseView{}, tierAtLeast, running),
+		"mesh-catalog #175 a tap shows its outcome · messenger, telegram → novox · tier 1 of 1, building for 2m0s"; got != want {
+		t.Fatalf("the line reads %q, want %q", got, want)
+	}
+	if got := planLine(p, now); !strings.HasPrefix(got, "mesh-catalog #175 a tap shows its outcome · messenger, telegram · tier") {
+		t.Fatalf("without the machines the line reads %q", got)
+	}
+	old := p
+	old.Commits, old.Delivery = nil, nil
+	if got := planLine(old, now); !strings.HasPrefix(got, "mesh-catalog c1c1c1c1 · tier 1 of 1") {
+		t.Fatalf("a record naming no pull request reads %q", got)
+	}
+	long := p
+	long.Delivery.Merges[0].Title = strings.Repeat("abcdefghij", 6)
+	if got := planHeadline(long, nil); !strings.Contains(got, "#175 "+strings.Repeat("abcdefghij", 4)+"abcdefghi…") {
+		t.Fatalf("a long title is not cut at fifty runes: %q", got)
+	}
+}
+
+// sameMerge compares what a walk names of a merge: its repository, commit and the commit carrying it.
+func sameMerge(a, b inventory.PlanMerge) bool {
+	return a.Repository == b.Repository && a.Commit == b.Commit && a.Carried == b.Carried
+}
+
+// A catalogue merge heard after a later merge of its branch was walked without the word (a merge that touched
+// the bus too, on the controller's own path) is not answered by that walk while the delivery seat has a holder:
+// its delivery would skip its turn. It joins the next catalogue batch.

cmd/mesh-controller/batches_watch.go

@@ -0,0 +1,153 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// **Every wait of a batch has a bound and a condition** (novox/hq ADR 0276 decision 9): a batch still
+// assembling a minute past its maximum while no walk is open is a cut the controller failed to make (S18),
+// and a batch waiting behind an open walk longer than that walk's bound waits on a walk gone wrong (S19).
+
+// The kinds S18 and S19 raise.
+const (
+	kindBatchNotCut     = "batch-not-cut"
+	kindBatchBehindWalk = "batch-behind-walk"
+	// kindGroupNotMerged is raised for a group whose last member has not merged by the merge window's maximum after
+	// its first (novox/hq ADR 0418 clause 3).
+	kindGroupNotMerged = "group-not-merged"
+)
+
+// batchFacts is one batch not yet cut, as the watchdogs read it.
+type batchFacts struct {
+	id, state, grouped string
+	// atMost is when its window closes at the latest; closed when it closed.
+	atMost, closed time.Time
+	// behind is the open walk it waits behind, and walkBound that walk's bound: a tier's bound for each of its
+	// tiers.
+	behind    string
+	walkBound time.Duration
+	// holds are the groups the batch is held for, by head, with why; created is when the batch was made, the first
+	// merge of the group heard; atMostWindow is the maximum a window may take (the controller's setting).
+	holds        map[string]string
+	created      time.Time
+	atMostWindow time.Duration
+}
+
+// gatherBatches is every batch not yet cut, with the bound of the walk it waits behind.
+func gatherBatches(ctx context.Context, inv *inventory.Inventory, now time.Time) ([]batchFacts, error) {
+	batches, err := inv.Batches(ctx)
+	if err != nil || len(batches) == 0 {
+		return nil, err
+	}
+	bounds, err := measuredTierBounds(ctx, inv, now)
+	if err != nil {
+		return nil, err
+	}
+	var out []batchFacts
+	for _, b := range batches {
+		_, atMostWindow := mergeWindowOf()
+		f := batchFacts{id: b.ID, state: b.State, grouped: groupedWords(b), created: b.Created, atMostWindow: atMostWindow}
+		if w := b.Delivery; w != nil && w.Batch != nil {
+			f.holds = w.Batch.Holds
+			f.atMost, f.closed, f.behind = w.Batch.AtMost, w.Batch.ClosesAt, w.Batch.Behind
+			if f.atMost.Before(f.closed) {
+				f.closed = f.atMost
+			}
+			if w.Batch.CutAtOnce && !b.Created.IsZero() {
+				// Its window closed when it was made, which is its latest too (ADR 0304 decision 1).
+				f.atMost, f.closed = b.Created, b.Created
+			}
+		}
+		if f.behind != "" {
+			if walk, err := inv.PlanByID(ctx, f.behind); err == nil {
+				f.walkBound = bounds.of(walk.Repository) * time.Duration(max(1, len(walk.Tiers)))
+			}
+		}
+		out = append(out, f)
+	}
+	return out, nil
+}
+
+// watchBatchesNotCut is S18: a batch still assembling a minute past its maximum, while no walk is open.
+func watchBatchesNotCut(f *signalFacts) []conditions.Observation {
+	var out []conditions.Observation
+	for _, b := range f.batches {
+		if b.state != inventory.PlanAssembling || b.atMost.IsZero() || f.now.Sub(b.atMost) <= batchLateAfter ||
+			len(b.holds) > 0 { // a batch held for a group waits on a member, which has its own condition
+			continue
+		}
+		late := f.now.Sub(b.atMost)
+		out = append(out, conditions.Observation{Scope: conditions.ScopePlan, ID: b.id, Kind: kindBatchNotCut,
+			Severity: conditions.Warning,
+			Summary: fmt.Sprintf("the batch %s is still assembling %s past its latest close (%s), with no walk open: "+
+				"the controller did not cut it; grouped: %s", b.id, ago(late), b.atMost.UTC().Format(time.RFC3339), b.grouped),
+			Said:     fmt.Sprintf("assembling since %s past its maximum", ago(late)),
+			Headline: "Merged changes are not being delivered",
+			Explanation: fmt.Sprintf("Merges collected for one delivery should have been planned %s ago and were not. "+
+				"Nothing is lost; the mesh keeps them until it plans them.", humanDuration(late)),
+			Resolved: "Merged changes are being delivered again"})
+	}
+	return out
+}
+
+// watchBatchesBehind is S19: a batch waiting behind an open walk longer than that walk's bound, naming it.
+func watchBatchesBehind(f *signalFacts) []conditions.Observation {
+	var out []conditions.Observation
+	for _, b := range f.batches {
+		if b.state != inventory.PlanQueued || b.behind == "" || b.walkBound <= 0 || f.now.Sub(b.closed) <= b.walkBound {
+			continue
+		}
+		in := f.now.Sub(b.closed)
+		out = append(out, conditions.Observation{Scope: conditions.ScopePlan, ID: b.id, Kind: kindBatchBehindWalk,
+			Severity: conditions.Warning,
+			Summary: fmt.Sprintf("the batch %s has waited %s behind the walk %s, longer than that walk's bound (%s); "+
+				"grouped: %s; `plans %s` says where that walk stands", b.id, ago(in), b.behind, ago(b.walkBound),
+				b.grouped, b.behind),
+			Said:     fmt.Sprintf("queued behind %s for %s", b.behind, ago(in)),
+			Headline: "Merged changes wait behind a slow delivery",
+			Explanation: fmt.Sprintf("Merges collected for the next delivery have waited %s for the delivery before "+
+				"them, which is taking longer than it should. Nothing is lost.", humanDuration(in)),
+			Resolved: "Merged changes no longer wait behind a slow delivery"})
+	}
+	return out
+}
+
+// watchGroupsNotMerged is the condition of a batch held for a group whose last member has not merged by the merge
+// window's maximum after the first member merged, naming the member and why (novox/hq ADR 0418 clause 3): nothing of
+// the group is delivered while it waits.
+func watchGroupsNotMerged(f *signalFacts) []conditions.Observation {
+	var out []conditions.Observation
+	for _, b := range f.batches {
+		if len(b.holds) == 0 || b.created.IsZero() || f.now.Sub(b.created) <= b.atMostWindow {
+			continue
+		}
+		heads := make([]string, 0, len(b.holds))
+		for h := range b.holds {
+			heads = append(heads, h)
+		}
+		sort.Strings(heads)
+		var why []string
+		for _, h := range heads {
+			why = append(why, b.holds[h])
+		}
+		waited := f.now.Sub(b.created)
+		out = append(out, conditions.Observation{Scope: conditions.ScopePlan, ID: b.id,
+			Kind: kindGroupNotMerged, Severity: conditions.Warning,
+			Summary: fmt.Sprintf("%s; its first member merged %s ago, past the merge window's maximum (%s), and nothing "+
+				"of the group is delivered while it waits (batch %s)", strings.Join(why, "; "), ago(waited), ago(b.atMostWindow), b.id),
+			Said:     "a group waits for a member that has not merged",
+			Headline: "A change waits for the rest of its group to merge",
+			Explanation: fmt.Sprintf("The changes of a group are delivered together, once the last one is merged. "+
+				"One has not merged in %s. Nothing is lost; the merged ones are kept and delivered with it.",
+				humanDuration(waited)),
+			Resolved: "The group's last change merged"})
+	}
+	return out
+}

cmd/mesh-controller/beside_test.go

@@ -0,0 +1,108 @@
+//go:build integration
+
+package main
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// An unrelated closed batch is cut into a walk beside an open one, and that walk asks its first tier at once
+// (issue 973, novox/hq ADR 0407 decision 4): a hotfix is never held by an unrelated delivery.
+func TestAnUnrelatedBatchWalksBesideAnOpenWalk(t *testing.T) {
+	open := windowed(t)
+	asksWithPaths(t)
+	ctx := t.Context()
+	hear(t, open, repoMerge("one", "c1", t0), t0)
+	cutAt(t, open, t0.Add(90*time.Second))
+	if ws, _ := walks(t, open); len(ws) != 1 || !ws[0].Open() {
+		t.Fatalf("the first walk is not open: %+v", ws)
+	}
+	heard := t0.Add(100 * time.Second)
+	hear(t, open, lone(repoMerge("two", "c2", heard)), heard)
+	advanceHeld(ctx, open)
+	ws, bs := walks(t, open)
+	if len(ws) != 2 || len(bs) != 0 {
+		t.Fatalf("%d walk(s) and %d batch(es); want the unrelated batch cut beside the open walk", len(ws), len(bs))
+	}
+	for _, w := range ws {
+		if !w.Open() || w.Waiting() || deferred(w) || !askedAny(w) {
+			t.Errorf("%s (%s) is not walking: open %v, deferred %v, asked %v, note %q", w.ID, w.Named(), w.Open(),
+				deferred(w), askedAny(w), w.Note)
+		}
+	}
+}
+
+// A closed batch related to an open walk is queued behind it with the reason, while one that shares nothing is
+// cut beside it; the walk that started is never superseded (ADR 0276 decision 4, issue 973).
+func TestARelatedBatchWaitsBehindTheOpenWalk(t *testing.T) {
+	open := windowed(t)
+	asksWithPaths(t)
+	ctx := t.Context()
+	hear(t, open, repoMerge("one", "c1", t0), t0)
+	cutAt(t, open, t0.Add(90*time.Second))
+	first := func() inventory.Plan { ws, _ := walks(t, open); return ws[len(ws)-1] }()
+	heard := t0.Add(100 * time.Second)
+	hear(t, open, lone(repoMerge("one", "c2", heard)), heard)
+	hear(t, open, lone(repoMerge("three", "c3", heard.Add(time.Second))), heard.Add(time.Second))
+	ws, bs := walks(t, open)
+	if len(ws) != 2 || len(bs) != 1 {
+		t.Fatalf("%d walk(s) and %d batch(es); want the unrelated merge walking and the related one queued", len(ws), len(bs))
+	}
+	b := bs[0]
+	words := batchWords(b, heard)
+	if b.State != inventory.PlanQueued || b.Delivery.Batch.Behind != first.ID || b.CommitOf("novox/one") != "c2" ||
+		!strings.Contains(words, "queued behind "+first.ID) || !strings.Contains(words, "both change novox/one") {
+		t.Fatalf("the related batch is %s, behind %q, reading %q", b.State, b.Delivery.Batch.Behind, words)
+	}
+	if got, _ := open.inventory.PlanByID(ctx, first.ID); !got.Open() {
+		t.Fatalf("the started walk was %s by the related merge", got.State)
+	}
+	first.State = inventory.PlanDone
+	if err := open.inventory.SavePlan(ctx, &first); err != nil {
+		t.Fatal(err)
+	}
+	cutAt(t, open, heard.Add(2*time.Second))
+	if _, bs := walks(t, open); len(bs) != 0 {
+		t.Fatalf("the queued batch was not cut once the walk it waited for ended: %+v", bs)
+	}
+}
+
+// A batch on the controller's own path never walks beside another walk, and nothing walks beside it, whatever
+// the two share (issue 973): it replaces the controller, so it goes alone.
+func TestAnOwnPathBatchNeverWalksBeside(t *testing.T) {
+	open := windowed(t)
+	asksWithPaths(t)
+	ctx := t.Context()
+	hear(t, open, repoMerge("one", "c1", t0), t0)
+	cutAt(t, open, t0.Add(90*time.Second))
+	ws, _ := walks(t, open)
+	first := ws[0]
+	heard := t0.Add(100 * time.Second)
+	hear(t, open, lone(repoMerge("mesh-controller", "k1", heard)), heard)
+	ws, bs := walks(t, open)
+	if len(ws) != 1 || len(bs) != 1 || !bs[0].OwnPath() || bs[0].State != inventory.PlanQueued ||
+		bs[0].Delivery.Batch.Behind != first.ID || !strings.Contains(batchWords(bs[0], heard), "own path") {
+		t.Fatalf("an own-path batch beside an open walk: %d walk(s), batches %+v", len(ws), bs)
+	}
+	first.State = inventory.PlanDone
+	if err := open.inventory.SavePlan(ctx, &first); err != nil {
+		t.Fatal(err)
+	}
+	cutAt(t, open, heard.Add(time.Second))
+	ws, _ = walks(t, open)
+	if len(ws) != 2 || !ws[0].Open() || ws[0].CommitOf("novox/mesh-controller") != "k1" {
+		t.Fatalf("the own-path batch was not cut once the walk ended: %+v", ws)
+	}
+	own := ws[0]
+	// Unrelated to the own-path walk by every footprint, a merge still waits for it.
+	later := heard.Add(time.Minute)
+	hear(t, open, lone(repoMerge("two", "c2", later)), later)
+	ws, bs = walks(t, open)
+	if len(ws) != 2 || len(bs) != 1 || bs[0].State != inventory.PlanQueued || bs[0].Delivery.Batch.Behind != own.ID {
+		t.Fatalf("a merge beside the own-path walk: %d walk(s), batches %+v", len(ws), bs)
+	}
+}

cmd/mesh-controller/bindings.go

@@ -0,0 +1,140 @@
+package main
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/conditions"
+)
+
+// A binding to data moves only by a person (novox/hq ADR 0232, issue 273).
+//
+// The resolver keeps each consumer of a provision that keeps its data at the provider it was last
+// sent (catalogue/bound.go) and says what it would have moved. This is where that is said: on the
+// push that composed it, and by the self-check's D12 every run, as an urgent condition naming the
+// consumer, both providers and the pin that confirms the move.
+
+// The condition kinds of D12.
+const (
+	// kindBindingKept is a move the resolver refused: the consumer is still where its data is.
+	kindBindingKept = "binding-kept"
+	// kindBindingMoved is a consumer about to be sent another provider than the one on record with
+	// no pin naming it — what the resolver exists to make impossible, said if it ever is not.
+	kindBindingMoved = "binding-moved"
+	// kindBindingMoving is a move a pin asked for, not yet sent: a person's act, said so that the
+	// data is moved before the push that carries it.
+	kindBindingMoving = "binding-moving"
+)
+
+// probeBindingsID is the self-check's id for this probe, and the source of what it raises.
+const probeBindingsID = "D12"
+
+// keptObservation is the urgent condition for one refused move.
+func keptObservation(k catalogue.KeptBinding) conditions.Observation {
+	return conditions.Observation{Scope: conditions.ScopeMachine, ID: bindingID(k.Machine, k.Consumer, k.Provision),
+		Token: kindBindingKept, Kind: kindBindingKept, Machine: k.Machine, Also: otherMachines(k.Machine, k.Bound.Node, k.Would.Node),
+		Severity: conditions.Urgent, Resolver: conditions.ResolverOperator,
+		Summary: fmt.Sprintf("on %s, the mesh %s", k.Machine, k.String())}
+}
+
+func bindingID(machine, consumer, provision string) string {
+	return machine + "." + consumer + "." + provision
+}
+
+func otherMachines(machine string, nodes ...string) []string {
+	var out []string
+	seen := map[string]bool{machine: true}
+	for _, n := range nodes {
+		if n != "" && !seen[n] {
+			seen[n] = true
+			out = append(out, n)
+		}
+	}
+	return out
+}
+
+// reportKept says every move a machine's resolution refused, on the push composing it, and raises its
+// condition at once where this process keeps the conditions: a push is when a person is looking.
+func reportKept(ctx context.Context, plan catalogue.Resolution) {
+	for _, k := range plan.Kept {
+		fmt.Printf("%s: the mesh %s\n", plan.Node, k)
+		if conditionsFrom != nil {
+			o := keptObservation(k)
+			o.Source = probeBindingsID
+			if _, err := conditionsFrom.Observe(ctx, o); err != nil {
+				fmt.Printf("%s: and the condition for it could not be raised: %v\n", plan.Node, err)
+			}
+		}
+	}
+}
+
+// probeBindings is D12: every consumer of a provision that keeps its data is bound where it was last
+// sent, on every machine — the resolver kept it there (said, urgent, until a person pins), or a pin
+// moves it (said, so the data goes first), and never anything else.
+func probeBindings(ctx context.Context, d *doctor) ([]conditions.Observation, error) {
+	inv := d.open.inventory
+	nodes, err := inv.Nodes(ctx)
+	if err != nil {
+		return nil, err
+	}
+	var out []conditions.Observation
+	for _, n := range nodes {
+		plan, _, err := planFor(ctx, d.open, n.Name)
+		if err != nil {
+			if unresolvable(err) {
+				// D1 says it, with the binding that refused it when that is why.
+				continue
+			}
+			return nil, fmt.Errorf("%s cannot be worked out: %w", n.Name, err)
+		}
+		bound, err := inv.BindingsFor(ctx, n.Name)
+		if err != nil {
+			return nil, err
+		}
+		pins, err := inv.PinsFor(ctx, n.Name)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, bindingFindings(plan, bound, pins)...)
+	}
+	return out, nil
+}
+
+// bindingFindings is what one machine's resolution says against its record.
+func bindingFindings(plan catalogue.Resolution, bound map[string]map[string]catalogue.Chosen,
+	pins map[string]catalogue.Chosen) []conditions.Observation {
+	var out []conditions.Observation
+	for _, k := range plan.Kept {
+		out = append(out, keptObservation(k))
+	}
+	said := map[string]bool{}
+	for _, need := range plan.Needs {
+		if !need.KeepsData || need.ByRecord {
+			continue
+		}
+		was, recorded := bound[need.For][need.Name]
+		now := catalogue.Chosen{Node: need.From, Module: need.Module}
+		if !recorded || was == now || (was.Module == "" && was.Node == now.Node) {
+			continue
+		}
+		id := bindingID(plan.Node, need.For, need.Name)
+		if said[id] {
+			continue
+		}
+		said[id] = true
+		o := conditions.Observation{Scope: conditions.ScopeMachine, ID: id, Machine: plan.Node,
+			Also: otherMachines(plan.Node, was.Node, now.Node), Resolver: conditions.ResolverOperator}
+		if pin, pinned := pins[need.Name]; pinned && pin.Node == now.Node && (pin.Module == "" || pin.Module == now.Module) {
+			o.Token, o.Kind, o.Severity = kindBindingMoving, kindBindingMoving, conditions.Warning
+			o.Summary = fmt.Sprintf("on %s, %s's %s moves from %s to %s at the next push, by the pin — its data "+
+				"is on %s: move it first", plan.Node, need.For, need.Name, was, now, was)
+		} else {
+			o.Token, o.Kind, o.Severity = kindBindingMoved, kindBindingMoved, conditions.Urgent
+			o.Summary = fmt.Sprintf("on %s, %s's %s would be sent %s, and it is bound to %s, where its data is, "+
+				"with no pin naming %s — a move nothing asked for", plan.Node, need.For, need.Name, now, was, now)
+		}
+		out = append(out, o)
+	}
+	return out
+}

cmd/mesh-controller/bindings_integration_test.go

@@ -0,0 +1,102 @@
+//go:build integration
+
+package main
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/conditions"
+)
+
+func TestTheIncidentAConsumerStaysBesideItsDataUntilAPersonPinsIt(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	inv := open.inventory
+	if _, err := inv.SeedSeats(ctx, catalogue.DefaultSeats()); err != nil {
+		t.Fatal(err)
+	}
+	for _, m := range storeManifests() {
+		register(t, open, m)
+	}
+	assignAll := func(pairs ...[2]string) {
+		for _, a := range pairs {
+			if _, err := assign(ctx, open, a[0], a[1]); err != nil {
+				t.Fatalf("assign %s %s: %v", a[0], a[1], err)
+			}
+		}
+	}
+	// The anchor's store and resolver hold the mesh's seats, on record; the laptop runs its own of each.
+	assignAll([2]string{"anchor", "store"}, [2]string{"anchor", "resolver"})
+	for _, seat := range [][2]string{{"mesh-store", "store"}, {"mesh-dns-resolver", "resolver"}} {
+		if err := inv.HoldSeat(ctx, seat[0], catalogue.ScopeMesh, "anchor", seat[1]); err != nil {
+			t.Fatal(err)
+		}
+	}
+	assignAll([2]string{"laptop", "store"}, [2]string{"laptop", "resolver"}, [2]string{"laptop", "network"},
+		[2]string{"laptop", "board"})
+
+	plan, _, err := planFor(ctx, open, "laptop")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n := need(t, plan, "board", "postgres-database"); n.From != "laptop" || n.Module != "store" || !n.KeepsData {
+		t.Fatalf("the consumer was bound to %s/%s (keeps data: %v); its data is beside it", n.From, n.Module, n.KeepsData)
+	}
+	if n := need(t, plan, "network", "wildcard-resolution"); n.From != "anchor" || n.KeepsData {
+		t.Fatalf("the resolver was bound to %s (keeps data: %v); its seat is held on anchor (issue 258)", n.From, n.KeepsData)
+	}
+
+	// Sent, and recorded: only the binding to data.
+	bindings := boundToData(plan, nil)
+	if len(bindings) != 1 || bindings[0].Provider != (catalogue.Chosen{Node: "laptop", Module: "store"}) {
+		t.Fatalf("recorded %+v", bindings)
+	}
+	if err := inv.RecordBindings(ctx, "laptop", bindings); err != nil {
+		t.Fatal(err)
+	}
+	if found, err := probeBindings(ctx, &doctor{open: open}); err != nil || len(found) != 0 {
+		t.Fatalf("a mesh bound where it was sent: %+v, %v", found, err)
+	}
+
+	// The laptop's store taken away: refused, not moved to the anchor's empty one.
+	if err := inv.Unassign(ctx, "laptop", "store"); err != nil {
+		t.Fatal(err)
+	}
+	if _, _, err := planFor(ctx, open, "laptop"); err == nil || !unresolvable(err) ||
+		!strings.Contains(err.Error(), "board on laptop is bound to laptop/store") ||
+		!strings.Contains(err.Error(), "pin laptop postgres-database anchor store") {
+		t.Fatalf("the consumer's store went and it was answered elsewhere: %v", err)
+	}
+
+	// A person pins the anchor's: it moves, said before it is sent, and the record keeps where it was.
+	if err := inv.PinProvision(ctx, "laptop", "postgres-database", "anchor", "store"); err != nil {
+		t.Fatal(err)
+	}
+	plan, _, err = planFor(ctx, open, "laptop")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n := need(t, plan, "board", "postgres-database"); n.From != "anchor" {
+		t.Fatalf("pinned to the anchor and bound to %s", n.From)
+	}
+	found, err := probeBindings(ctx, &doctor{open: open})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(found) != 1 || found[0].Kind != kindBindingMoving || found[0].Severity != conditions.Warning ||
+		!strings.Contains(found[0].Summary, "board's postgres-database moves from laptop/store to anchor/store") {
+		t.Fatalf("a pinned move is not said before it is sent: %+v", found)
+	}
+	if err := inv.RecordBindings(ctx, "laptop", boundToData(plan, nil)); err != nil {
+		t.Fatal(err)
+	}
+	all, err := inv.Bindings(ctx)
+	if err != nil || len(all) != 1 || all[0].MovedFrom != "laptop/store" {
+		t.Fatalf("%+v, %v", all, err)
+	}
+	if found, err := probeBindings(ctx, &doctor{open: open}); err != nil || len(found) != 0 {
+		t.Fatalf("a move sent is still said: %+v, %v", found, err)
+	}
+}

cmd/mesh-controller/bindings_test.go

@@ -0,0 +1,93 @@
+package main
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/conditions"
+)
+
+// novox/hq issue 273, ADR 0232: a consumer of a provision that keeps its data moves only by a pin.
+
+func storeManifests() []catalogue.Manifest {
+	return []catalogue.Manifest{
+		{Module: "store", Version: "1",
+			Provides: []catalogue.Offer{{Name: "postgres-database", Scope: catalogue.ScopeMesh}},
+			Claims:   []catalogue.Claim{{Name: "mesh-store", Scope: catalogue.ScopeMesh}},
+			Serves:   map[string]map[string]any{"postgres-database": {"port": 5432}},
+			Grants:   map[string]string{"postgres-database": "/var/lib/mesh/store/grants"}},
+		{Module: "resolver", Version: "1",
+			Provides: []catalogue.Offer{{Name: "wildcard-resolution", Scope: catalogue.ScopeMesh}},
+			Claims:   []catalogue.Claim{{Name: "mesh-dns-resolver", Scope: catalogue.ScopeMesh}}},
+		{Module: "network", Version: "1", Requires: []string{"wildcard-resolution"}},
+		{Module: "board", Version: "1", Requires: []string{"postgres-database"}},
+	}
+}
+
+func need(t *testing.T, plan catalogue.Resolution, consumer, provision string) catalogue.Needed {
+	t.Helper()
+	for _, n := range plan.Needs {
+		if n.For == consumer && n.Name == provision {
+			return n
+		}
+	}
+	t.Fatalf("no %s for %s: %+v", provision, consumer, plan.Needs)
+	return catalogue.Needed{}
+}
+
+// The incident through the stores: the laptop runs its own store and a consumer of it, the anchor's
+// store holds the mesh's seat. The consumer stays beside its data, the resolver follows its seat, the
+// binding is recorded as sent, and a pin — only a pin — moves it, said before the push that carries it.
+
+// What one machine's resolution says against its record.
+func TestBindingFindingsSayAKeptMoveAndAMoveNothingAskedFor(t *testing.T) {
+	home, anchor := catalogue.Chosen{Node: "home", Module: "store"}, catalogue.Chosen{Node: "anchor", Module: "store"}
+	plan := catalogue.Resolution{Node: "laptop",
+		Kept: []catalogue.KeptBinding{{Machine: "laptop", Consumer: "board", Provision: "postgres-database",
+			Bound: home, Would: anchor}},
+		Needs: []catalogue.Needed{
+			{Name: "postgres-database", For: "board", From: "home", Module: "store", KeepsData: true},
+			{Name: "postgres-database", For: "game", From: "anchor", Module: "store", KeepsData: true},
+			{Name: "wildcard-resolution", For: "network", From: "anchor", Module: "resolver"},
+		}}
+	bound := map[string]map[string]catalogue.Chosen{
+		"board":   {"postgres-database": home},
+		"game":    {"postgres-database": home},
+		"network": {"wildcard-resolution": {Node: "home", Module: "resolver"}},
+	}
+	found := linted(bindingFindings(plan, bound, nil))
+	if len(found) != 2 {
+		t.Fatalf("found %+v", found)
+	}
+	kept, moved := found[0], found[1]
+	if kept.Kind != kindBindingKept || kept.Severity != conditions.Urgent || kept.Machine != "laptop" ||
+		!strings.Contains(kept.Summary, "would move board's postgres-database from home/store to anchor/store") ||
+		!strings.Contains(kept.Summary, "its data is on home/store") ||
+		!strings.Contains(kept.Summary, "`pin laptop postgres-database anchor store` to confirm a move (and move the data first)") {
+		t.Errorf("kept: %+v", kept)
+	}
+	if moved.Kind != kindBindingMoved || moved.Severity != conditions.Urgent ||
+		!strings.Contains(moved.Summary, "game's postgres-database would be sent anchor/store") {
+		t.Errorf("moved: %+v", moved)
+	}
+	if kept.Key() == moved.Key() {
+		t.Error("two consumers, one condition")
+	}
+}
+
+// A push says the move it refused, and raises its condition at once.
+func TestAPushSaysAKeptMoveAndRaisesItsCondition(t *testing.T) {
+	k, _ := withConditionsInMemory(t)
+	reportKept(t.Context(), catalogue.Resolution{Node: "laptop", Kept: []catalogue.KeptBinding{{Machine: "laptop",
+		Consumer: "board", Provision: "postgres-database", Bound: catalogue.Chosen{Node: "home", Module: "store"},
+		Would: catalogue.Chosen{Node: "anchor", Module: "store"}}}})
+	open, err := k.Open(t.Context())
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(open) != 1 || open[0].Kind != kindBindingKept || open[0].Severity != conditions.Urgent ||
+		open[0].Source != probeBindingsID {
+		t.Fatalf("raised %+v", open)
+	}
+}

cmd/mesh-controller/board.go

@@ -137,6 +137,9 @@ type view struct {
 	Unresolved []blockedMachine
 	// Network is why the private network could not be computed, when it could not.
 	Network string
+	// Adopted is every node still adopted (novox/hq ADR 0100). Not broken: nothing forces the
+	// flip, so a node left adopted is shown rather than read as converged.
+	Adopted []string
 	At      string
 }
 
@@ -181,7 +184,7 @@ type staleModule struct {
 
 func viewOf(asked answers) view {
 	out := view{Machines: len(asked.nodes), At: time.Now().Format("15:04:05"),
-		Network: asked.network}
+		Network: asked.network, Adopted: adoptedNodes(asked.nodes)}
 	var blocked []string
 	for name := range asked.refused {
 		blocked = append(blocked, name)
@@ -311,6 +314,10 @@ new, switched off, or unreachable.</p>
 <p class="quiet">Never told is not out of date: nobody has asked that machine to be anything yet.
 Both are sent by <code>push --behind</code>.</p>
 {{else}}<p class="quiet">Every machine is running what the mesh would send it.</p>{{end}}
+{{if .Adopted}}
+<h2>Which machines are adopted?</h2>
+<ul>{{range .Adopted}}<li><strong>{{.}}</strong> <span class="quiet">adopted — what was found on it is kept until each module is taken</span></li>{{end}}</ul>
+{{end}}
 {{end}}
 
 <footer>Read at {{.At}}. This page holds nothing and changes nothing.</footer>

cmd/mesh-controller/bucket_log_fill.go

@@ -0,0 +1,207 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"sort"
+
+	"github.com/nats-io/nats.go"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+)
+
+// **A filling bucket or log is said before it is full** (novox/hq ADR 0297 §6, issue 501).
+//
+// A module's bucket and its log each have a cap on the bus, and when either is full the bus refuses
+// the next write: the module stops doing what it writes for, and nothing said so before. On
+// 2026-10-11 the issue tracker's bucket held a sixth of its cap after two days, growing toward a stop
+// nobody would have heard coming. So the self-check reads every module's bucket and log, and one at
+// fillRaiseAt of its cap or more raises a condition naming the module, the bucket or log, and how full
+// it is.
+//
+// **Cleared by observation below fillClearBelow, not below fillRaiseAt**: a bucket or log hovering at
+// its threshold would otherwise be raised and cleared on every run. Between the two, an open condition
+// is kept and none is raised.
+//
+// **One that cannot be read is said, and the rest are still judged.** An unanswered question about one
+// stream is no reason to know nothing of the others: it is a finding of its own, naming the bucket or
+// log and why, and a fill condition already open for it is kept, because not knowing is not a pass.
+
+// The fill thresholds, in percent of a bucket's or log's cap.
+const (
+	fillRaiseAt    = 75
+	fillClearBelow = 70
+)
+
+// The conditions the fill probe raises: one filling, and one that could not be read.
+const (
+	kindBucketOrLogFilling = "bucket-or-log-filling"
+	kindBucketOrLogUnread  = "bucket-or-log-unread"
+)
+
+// probeFillID is the probe's id in the registry.
+const probeFillID = "D-fill"
+
+// bucketOrLog is one module's bucket or log as the fill probe reads it.
+type bucketOrLog struct {
+	Module string
+	// Kind is `bucket` or `log`; Name its local name; Stream the stream it is on the bus.
+	Kind, Name, Stream string
+}
+
+// filled is how full one bucket or log is, read from the bus.
+type filled struct {
+	Bytes, Max uint64
+}
+
+// percent is how full, in whole percent, rounded down.
+func (f filled) percent() uint64 {
+	if f.Max == 0 {
+		return 0
+	}
+	return f.Bytes * 100 / f.Max
+}
+
+// fillKey is where a bucket's or log's fill condition is kept.
+func fillKey(s bucketOrLog) string { return conditions.Key(conditions.ScopeBus, s.Stream, "filling") }
+
+// fillObservation is what one bucket's or log's fill says: a finding at fillRaiseAt or above, and,
+// while its condition is open, at fillClearBelow or above too; nothing otherwise, which is what clears
+// it. The operator's words are the kind's (plain_words.go); the summary and the evidence name the
+// module, the bucket or log, and the fill.
+func fillObservation(s bucketOrLog, f filled, open bool) (conditions.Observation, bool) {
+	if f.Max == 0 {
+		return conditions.Observation{}, false // one with no cap cannot fill
+	}
+	// Compared in bytes, not rounded percent: 74.9% is not 75%.
+	atRaise := f.Bytes*100 >= f.Max*fillRaiseAt
+	aboveClear := f.Bytes*100 >= f.Max*fillClearBelow
+	if !atRaise && !(open && aboveClear) {
+		return conditions.Observation{}, false
+	}
+	pct := f.percent()
+	return conditions.Observation{
+		Scope: conditions.ScopeBus, ID: s.Stream, Token: "filling", Kind: kindBucketOrLogFilling,
+		Severity: conditions.Warning,
+		Summary: fmt.Sprintf("%s's %s %s holds %s of %s, %d%%: at its cap the bus refuses the module's next write",
+			s.Module, s.Kind, s.Name, mibWords(f.Bytes), mibWords(f.Max), pct),
+		Said: fmt.Sprintf("module %s, %s %s (stream %s): %d of %d bytes, %d%%", s.Module, s.Kind, s.Name,
+			s.Stream, f.Bytes, f.Max, pct),
+	}, true
+}
+
+// unreadObservation says one bucket or log could not be read, and why. Asked over the network, so one
+// look can be wrong: raised on the second look in a row (confirm.go).
+func unreadObservation(s bucketOrLog, why error) conditions.Observation {
+	return conditions.Observation{
+		Scope: conditions.ScopeBus, ID: s.Stream, Token: "unread", Kind: kindBucketOrLogUnread,
+		Severity: conditions.Warning, Confirm: true,
+		Summary: fmt.Sprintf("%s's %s %s could not be read, so how full it is is not known", s.Module, s.Kind, s.Name),
+		Said:    fmt.Sprintf("module %s, %s %s (stream %s): %v", s.Module, s.Kind, s.Name, s.Stream, why),
+	}
+}
+
+// keptFilling is an open fill condition said again for a bucket or log that could not be read this
+// time: not knowing how full it is now is no reason to say it has room. Only ever made from a condition
+// read back as open — its own summary and severity, never words made up for it.
+func keptFilling(s bucketOrLog, open conditions.Condition, why error) conditions.Observation {
+	return conditions.Observation{
+		Scope: conditions.ScopeBus, ID: s.Stream, Token: "filling", Kind: kindBucketOrLogFilling,
+		Severity: open.Severity, Summary: open.Summary,
+		Said: fmt.Sprintf("module %s, %s %s (stream %s): not read this time (%v); kept open as it was",
+			s.Module, s.Kind, s.Name, s.Stream, why),
+	}
+}
+
+// mibWords is a size as a person reads it, in MiB with one decimal.
+func mibWords(b uint64) string {
+	return fmt.Sprintf("%.1f MiB", float64(b)/(1024*1024))
+}
+
+// readFill is how full one bucket or log is on the bus; found false when it is not on the bus.
+type readFill func(ctx context.Context, s bucketOrLog) (f filled, found bool, err error)
+
+// openFill is the fill condition open under a key, if one is, or why it could not be read.
+type openFill func(ctx context.Context, key string) (conditions.Condition, bool, error)
+
+// judgeFills judges every bucket and log on its own: one that cannot be read is said as unread, with
+// its fill condition kept only when that condition was read back and is open — when it cannot be read
+// either, nothing is said of its fill, which the unread finding already covers. Every other is judged
+// by its fill; for one of those, a condition that cannot be read is taken as open, so an unknown never
+// clears a fill measured between fillClearBelow and fillRaiseAt.
+func judgeFills(ctx context.Context, all []bucketOrLog, read readFill, open openFill) []conditions.Observation {
+	var out []conditions.Observation
+	for _, s := range all {
+		f, found, err := read(ctx, s)
+		if err != nil {
+			out = append(out, unreadObservation(s, err))
+			if c, isOpen, cerr := open(ctx, fillKey(s)); cerr == nil && isOpen {
+				out = append(out, keptFilling(s, c, err))
+			}
+			continue
+		}
+		if !found {
+			continue // not on the bus: created on the controller's next raise, and nothing there can fill
+		}
+		_, isOpen, cerr := open(ctx, fillKey(s))
+		isOpen = isOpen || cerr != nil
+		if o, said := fillObservation(s, f, isOpen); said {
+			out = append(out, o)
+		}
+	}
+	sort.SliceStable(out, func(i, j int) bool { return out[i].Key() < out[j].Key() })
+	return out
+}
+
+// declaredBucketsAndLogs is every module's bucket and log the catalogue declares, by its stream.
+func declaredBucketsAndLogs(ctx context.Context, d *doctor) ([]bucketOrLog, error) {
+	buckets, err := d.open.inventory.DeclaredBuckets(ctx)
+	if err != nil {
+		return nil, err
+	}
+	logs, err := d.open.inventory.DeclaredLogs(ctx)
+	if err != nil {
+		return nil, err
+	}
+	var out []bucketOrLog
+	for _, b := range buckets {
+		out = append(out, bucketOrLog{Module: b.Module, Kind: "bucket", Name: b.Name, Stream: "KV_" + b.Bucket()})
+	}
+	for _, l := range logs {
+		out = append(out, bucketOrLog{Module: l.Module, Kind: "log", Name: l.Name, Stream: l.Stream()})
+	}
+	return out, nil
+}
+
+// probeFill reads every module's bucket and log on the bus and says each one filling toward its cap,
+// and each one that could not be read.
+func probeFill(ctx context.Context, d *doctor) ([]conditions.Observation, error) {
+	all, err := declaredBucketsAndLogs(ctx, d)
+	if err != nil {
+		return nil, err
+	}
+	js := d.js.Context()
+	read := func(ctx context.Context, s bucketOrLog) (filled, bool, error) {
+		if err := ctx.Err(); err != nil {
+			return filled{}, false, err
+		}
+		info, err := js.StreamInfo(s.Stream, nats.Context(ctx))
+		switch {
+		case errors.Is(err, nats.ErrStreamNotFound):
+			return filled{}, false, nil
+		case err != nil:
+			return filled{}, false, err
+		case info.Config.MaxBytes <= 0:
+			return filled{}, true, nil
+		}
+		return filled{Bytes: info.State.Bytes, Max: uint64(info.Config.MaxBytes)}, true, nil
+	}
+	open := func(ctx context.Context, key string) (conditions.Condition, bool, error) {
+		if d.keeper == nil {
+			return conditions.Condition{}, false, nil
+		}
+		return d.keeper.Get(ctx, key)
+	}
+	return judgeFills(ctx, all, read, open), nil
+}

cmd/mesh-controller/bucket_log_fill_test.go

@@ -0,0 +1,165 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+)
+
+// **A filling log or bucket is said at three quarters of its cap and cleared below seven tenths**
+// (novox/hq ADR 0297 §6): raised at 75% naming the module, the bucket or log and its fill; not at 74.9%;
+// kept between 70% and 75% while it is open, and not raised there when it is not; and cleared — said no
+// more — once it reads below 70%, open or not.
+func TestAFillingBucketOrLogIsRaisedAtThreeQuartersAndClearedBelowSevenTenths(t *testing.T) {
+	const mib = 1024 * 1024
+	log := bucketOrLog{Module: "mesh-issues", Kind: "log", Name: "changes", Stream: "LOG_mesh-issues_changes"}
+	bucket := bucketOrLog{Module: "mesh-issues", Kind: "bucket", Name: "issues", Stream: "KV_mesh-issues_issues"}
+	for _, c := range []struct {
+		name  string
+		of    bucketOrLog
+		bytes uint64
+		max   uint64
+		open  bool
+		said  bool
+	}{
+		{"a log at exactly 75%", log, 768 * mib, 1024 * mib, false, true},
+		{"a bucket at exactly 75%", bucket, 48 * mib, 64 * mib, false, true},
+		{"a bucket full", bucket, 64 * mib, 64 * mib, false, true},
+		{"a log just under 75%", log, 768*mib - 1, 1024 * mib, false, false},
+		{"a bucket at 72%, not open", bucket, 64 * mib * 72 / 100, 64 * mib, false, false},
+		{"a bucket at 72%, open: kept", bucket, 64 * mib * 72 / 100, 64 * mib, true, true},
+		{"a log at exactly 70%, open: kept", log, 700 * mib, 1000 * mib, true, true},
+		{"a log just under 70%, open: cleared", log, 700*mib - 1, 1000 * mib, true, false},
+		{"a bucket at 10%, open: cleared", bucket, 64 * mib / 10, 64 * mib, true, false},
+		{"a bucket with no cap", bucket, 100, 0, true, false},
+	} {
+		o, said := fillObservation(c.of, filled{Bytes: c.bytes, Max: c.max}, c.open)
+		if said != c.said {
+			t.Errorf("%s: said %v, want %v", c.name, said, c.said)
+			continue
+		}
+		if !said {
+			continue
+		}
+		if o.Key() != fillKey(c.of) || o.Kind != kindBucketOrLogFilling || o.Severity != conditions.Warning {
+			t.Errorf("%s: raised as %s (%s, %s)", c.name, o.Key(), o.Kind, o.Severity)
+		}
+		for _, part := range []string{c.of.Module, c.of.Kind + " " + c.of.Name, "%", " of "} {
+			if !strings.Contains(o.Summary, part) {
+				t.Errorf("%s: does not name %q: %q", c.name, part, o.Summary)
+			}
+		}
+		if !strings.Contains(o.Said, "bytes") {
+			t.Errorf("%s: the evidence does not say the fill in bytes: %q", c.name, o.Said)
+		}
+	}
+	o, _ := fillObservation(log, filled{Bytes: 800 * mib, Max: 1024 * mib}, false)
+	if !strings.Contains(o.Summary, "800.0 MiB of 1024.0 MiB, 78%") {
+		t.Errorf("the fill is said as %q", o.Summary)
+	}
+}
+
+// **One bucket or log that cannot be read does not stop the others being judged** (review of #231): it is
+// said as unread with its reason, a fill condition open for it is kept, and every other bucket and log
+// is judged by its own fill.
+func TestAnUnreadableBucketOrLogIsSaidAndTheRestAreStillJudged(t *testing.T) {
+	const mib = 1024 * 1024
+	broken := bucketOrLog{Module: "a", Kind: "bucket", Name: "broken", Stream: "KV_a_broken"}
+	brokenOpen := bucketOrLog{Module: "a", Kind: "log", Name: "was-filling", Stream: "LOG_a_was-filling"}
+	full := bucketOrLog{Module: "b", Kind: "log", Name: "changes", Stream: "LOG_b_changes"}
+	empty := bucketOrLog{Module: "c", Kind: "bucket", Name: "quiet", Stream: "KV_c_quiet"}
+	absent := bucketOrLog{Module: "d", Kind: "bucket", Name: "not-yet", Stream: "KV_d_not-yet"}
+	refusal := errors.New("the bus did not answer")
+	read := func(_ context.Context, s bucketOrLog) (filled, bool, error) {
+		switch s {
+		case broken, brokenOpen:
+			return filled{}, false, refusal
+		case full:
+			return filled{Bytes: 900 * mib, Max: 1000 * mib}, true, nil
+		case empty:
+			return filled{Bytes: 1, Max: 64 * mib}, true, nil
+		}
+		return filled{}, false, nil
+	}
+	open := func(_ context.Context, key string) (conditions.Condition, bool, error) {
+		if key == fillKey(brokenOpen) {
+			return conditions.Condition{Key: key, Severity: conditions.Warning,
+				Summary: "a's log was-filling holds 800.0 MiB of 1024.0 MiB, 78%"}, true, nil
+		}
+		return conditions.Condition{}, false, nil
+	}
+	got := map[string]conditions.Observation{}
+	for _, o := range judgeFills(context.Background(), []bucketOrLog{broken, brokenOpen, full, empty, absent}, read, open) {
+		got[o.Key()] = o
+	}
+	for _, s := range []bucketOrLog{broken, brokenOpen} {
+		o, said := got[conditions.Key(conditions.ScopeBus, s.Stream, "unread")]
+		if !said || o.Kind != kindBucketOrLogUnread || !o.Confirm || !strings.Contains(o.Said, refusal.Error()) {
+			t.Errorf("%s could not be read and was said as %+v", s.Stream, o)
+		}
+	}
+	if o, kept := got[fillKey(brokenOpen)]; !kept || !strings.Contains(o.Said, "kept open") {
+		t.Errorf("an open fill condition of a log not read this time was not kept: %+v", o)
+	}
+	if _, said := got[fillKey(broken)]; said {
+		t.Error("a bucket not read and not filling was said filling")
+	}
+	if o, said := got[fillKey(full)]; !said || o.Kind != kindBucketOrLogFilling {
+		t.Errorf("a log at 90%% beside an unreadable one was not judged: %+v", got)
+	}
+	if len(got) != 4 {
+		t.Errorf("said %d findings, want 4 (two unread, one kept, one filling): %v", len(got), got)
+	}
+}
+
+// Both kinds have plain words of their own, which hold to the plain rule (novox/hq ADR 0253).
+func TestAFillingOrUnreadBucketOrLogIsSaidInPlainWords(t *testing.T) {
+	for _, kind := range []string{kindBucketOrLogFilling, kindBucketOrLogUnread} {
+		wording, has := plainWordings[kind]
+		if !has {
+			t.Errorf("%s has no plain words", kind)
+			continue
+		}
+		if why, ok := conditions.PlainWords(wording(conditions.Observation{Kind: kind})); !ok {
+			t.Errorf("%s: %s", kind, why)
+		}
+	}
+}
+
+// **When neither the bucket or log nor its condition can be read, nothing is said of its fill** (second
+// review of #231): the unread finding covers it, and no fill is invented for it. For one that is read and
+// measured between seven tenths and three quarters, a condition that cannot be read is taken as open, so
+// an unknown never clears it.
+func TestNothingIsSaidOfAFillWhenNeitherItNorItsConditionCanBeRead(t *testing.T) {
+	const mib = 1024 * 1024
+	broken := bucketOrLog{Module: "a", Kind: "log", Name: "changes", Stream: "LOG_a_changes"}
+	between := bucketOrLog{Module: "b", Kind: "bucket", Name: "issues", Stream: "KV_b_issues"}
+	read := func(_ context.Context, s bucketOrLog) (filled, bool, error) {
+		if s == broken {
+			return filled{}, false, errors.New("the bus did not answer")
+		}
+		return filled{Bytes: 72 * mib, Max: 100 * mib}, true, nil
+	}
+	open := func(context.Context, string) (conditions.Condition, bool, error) {
+		return conditions.Condition{}, false, errors.New("the conditions bucket did not answer")
+	}
+	got := map[string]conditions.Observation{}
+	for _, o := range judgeFills(context.Background(), []bucketOrLog{broken, between}, read, open) {
+		got[o.Key()] = o
+	}
+	if o, said := got[fillKey(broken)]; said {
+		t.Fatalf("a fill was said for a log whose fill and condition could not be read: %+v", o)
+	}
+	if _, said := got[conditions.Key(conditions.ScopeBus, broken.Stream, "unread")]; !said {
+		t.Error("the log that could not be read was not said as unread")
+	}
+	if _, kept := got[fillKey(between)]; !kept {
+		t.Error("a bucket at 72% whose condition could not be read was cleared")
+	}
+	if len(got) != 2 {
+		t.Errorf("said %d findings, want 2: %v", len(got), got)
+	}
+}

cmd/mesh-controller/build_integration_test.go

@@ -0,0 +1,131 @@
+//go:build integration
+
+package main
+
+import (
+	"encoding/json"
+	"errors"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+func TestABuildHeardIsRecordedAndRegistered(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	manifest, _ := json.Marshal(map[string]any{"module": "shop", "version": "3"})
+	m, _, err := takeIn(ctx, open.inventory, asTheOperator(t, open.inventory, link.BuildResult{
+		ID: "b-1", Repository: "http://forge.internal:20000/novox/shop.git", Path: "modules/shop",
+		Ref: "main", On: "anchor", Commit: "abcdef0123", Manifest: manifest,
+		Source: &link.SourceOnSeat{Seat: "git", Repository: "novox/shop"},
+	}))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if m.Module != "shop" {
+		t.Fatalf("registered %q", m.Module)
+	}
+	shelf, err := open.inventory.Catalogue(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, held := shelf["shop"]; !held {
+		t.Fatal("the module a heard build produced is not in the catalogue")
+	}
+	src, err := open.inventory.SourceOf(ctx, "shop")
+	if err != nil || src.Seat != "git" || src.Repository != "novox/shop" || src.BuiltFrom != "abcdef0123" {
+		t.Fatalf("the source is the seat and the path, never the URL: %+v %v", src, err)
+	}
+	builds, err := open.inventory.Builds(ctx, "shop", 5)
+	if err != nil || len(builds) != 1 || builds[0].ID != "b-1" {
+		t.Fatalf("the build is not recorded once: %v %v", builds, err)
+	}
+
+	named, _ := json.Marshal(map[string]any{"module": "idp", "version": "1", "resources": []any{
+		map[string]any{"id": "server", "type": "container", "image": "x@sha256:aa",
+			"env": map[string]any{"KC_HOSTNAME": "https://login.mesh-one.be"}}}})
+	_, _, err = takeIn(ctx, open.inventory, link.BuildResult{
+		ID: "b-2", Repository: "/r", On: "anchor", Commit: "0123456789", Manifest: named})
+	if err == nil || !strings.Contains(err.Error(), "does not register it") {
+		t.Fatalf("a definition naming an installation was taken in: %v", err)
+	}
+	if shelf, _ := open.inventory.Catalogue(ctx); shelf["idp"].Module != "" {
+		t.Fatal("the refused module was registered anyway")
+	}
+	if builds, _ := open.inventory.Builds(ctx, "idp", 5); len(builds) != 1 {
+		t.Fatalf("the refused build was not recorded: %v", builds)
+	}
+
+	_, _, err = takeIn(ctx, open.inventory, link.BuildResult{ID: "b-3", Repository: "/r", On: "anchor", Failed: "no compiler"})
+	if err == nil || !strings.Contains(err.Error(), "no compiler") {
+		t.Fatalf("a failure is said in the builder's words: %v", err)
+	}
+}
+
+func TestABuildAtACommitKeepsTheBranchTheModuleFollows(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	manifest, _ := json.Marshal(map[string]any{"module": "unifi", "version": "1"})
+	result := func(id, ref, commit string) link.BuildResult {
+		return link.BuildResult{ID: id, Repository: "http://forge.internal:20000/novox/mesh-catalog.git",
+			Path: "modules/unifi", Ref: ref, On: "anchor", Commit: commit, Manifest: manifest,
+			Source: &link.SourceOnSeat{Seat: "git", Repository: "novox/mesh-catalog"}}
+	}
+	if _, _, err := takeIn(ctx, open.inventory, asTheOperator(t, open.inventory, result("b-1", "main", "1111111aaaa"))); err != nil {
+		t.Fatal(err)
+	}
+	if _, _, err := takeIn(ctx, open.inventory, result("b-2", "9c97a8a", "9c97a8a1d2c3")); err != nil {
+		t.Fatal(err)
+	}
+	src, err := open.inventory.SourceOf(ctx, "unifi")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if src.Ref != "main" || src.BuiltFrom != "9c97a8a1d2c3" {
+		t.Errorf("after a build at a commit the module follows %q, built from %q; want main, 9c97a8a1d2c3", src.Ref, src.BuiltFrom)
+	}
+
+	// One new to the catalogue, first built at a commit, follows the default branch.
+	other, _ := json.Marshal(map[string]any{"module": "letta", "version": "1"})
+	r := result("b-3", "deadbeef", "deadbeefcafe")
+	r.Manifest, r.Path = other, "modules/letta"
+	if _, _, err := takeIn(ctx, open.inventory, r); err != nil {
+		t.Fatal(err)
+	}
+	if src, _ := open.inventory.SourceOf(ctx, "letta"); src.Ref != "" {
+		t.Errorf("a module first built at a commit follows %q, want the default branch", src.Ref)
+	}
+}
+
+func TestAnOlderBuildHeardLaterDoesNotReplaceTheNewer(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	older := time.Date(2026, 10, 3, 21, 33, 45, 0, time.UTC)
+	newer := time.Date(2026, 10, 3, 21, 51, 57, 0, time.UTC)
+	result := func(asked time.Time, image string) link.BuildResult {
+		manifest, _ := json.Marshal(map[string]any{"module": "postgres", "version": image})
+		return link.BuildResult{ID: link.NewBuildID(asked), Repository: "http://forge.internal:20000/novox/mesh-catalog.git",
+			Path: "modules/postgres", Ref: "main", On: "anchor", Commit: "efff5415", Manifest: manifest,
+			Source: &link.SourceOnSeat{Seat: "git", Repository: "novox/mesh-catalog"}}
+	}
+	if _, _, err := takeIn(ctx, open.inventory, asTheOperator(t, open.inventory, result(newer, "4bcd5f73"))); err != nil {
+		t.Fatal(err)
+	}
+	_, _, err := takeIn(ctx, open.inventory, result(older, "0ab07fa9"))
+	if !errors.Is(err, inventory.ErrSuperseded) {
+		t.Fatalf("the older request's outcome was taken in as current: %v", err)
+	}
+	shelf, err := open.inventory.Catalogue(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got := shelf["postgres"].Version; got != "4bcd5f73" {
+		t.Errorf("postgres is %q; want the newer request's 4bcd5f73", got)
+	}
+	if builds, _ := open.inventory.Builds(ctx, "postgres", 5); len(builds) != 2 {
+		t.Errorf("the late build was not recorded: %v", builds)
+	}
+}

cmd/mesh-controller/build_seat_test.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+func claiming(module, seat string, on ...string) inventory.Entry {
+	return inventory.Entry{
+		Manifest: catalogue.Manifest{Module: module, Claims: []catalogue.Claim{{Name: seat}}},
+		On:       on,
+	}
+}
+
+// The controller asks the build role that has a holder (novox/hq ADR 0190 handover): the retired
+// one while only the builder is assigned, the current one from the first build-agent on, and the
+// current one when nothing holds either — where every ask goes once the handover is done.
+func TestTheControllerAsksTheBuildRoleThatHasAHolder(t *testing.T) {
+	onlyTheBuilder := []inventory.Entry{
+		claiming("builder", link.TheBuildMachineBefore, "anchor"),
+		claiming("build-agent", link.TheBuildMachine), // registered, assigned nowhere yet
+	}
+	if got := buildSeatAmong(onlyTheBuilder); got != link.TheBuildMachineBefore {
+		t.Errorf("with only the builder assigned, asked %q", got)
+	}
+	bothHeld := []inventory.Entry{
+		claiming("builder", link.TheBuildMachineBefore, "anchor"),
+		claiming("build-agent", link.TheBuildMachine, "home-server"),
+	}
+	if got := buildSeatAmong(bothHeld); got != link.TheBuildMachine {
+		t.Errorf("with a build-agent assigned anywhere, asked %q", got)
+	}
+	neither := []inventory.Entry{claiming("builder", link.TheBuildMachineBefore)}
+	if got := buildSeatAmong(neither); got != link.TheBuildMachine {
+		t.Errorf("with no holder of either, asked %q, want the current role", got)
+	}
+	if got := buildSeatAmong(nil); got != link.TheBuildMachine {
+		t.Errorf("an empty catalogue asks %q", got)
+	}
+}

cmd/mesh-controller/build_source.go

@@ -0,0 +1,594 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"os"
+	"regexp"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// Where a build may register a module from (novox/hq ADR 0266).
+//
+// A build's outcome registers its module, and a registered module is what the next push sends. Before this,
+// an outcome registered whatever its manifest named, from whichever repository it was built from: an agent
+// that made a repository of its own, committed `modules/sudo/module.json` granting itself a rule without a
+// password, and asked the `build` verb for it had its repository registered as the module `sudo` — whose next
+// push made the agent root on every node. A fork of the node-engine did the same everywhere. The trunk rule
+// (ADR 0238) did not stop it: the trunk it checked was the trunk of the repository built, which was the
+// agent's own.
+//
+// So **an outcome registers a module only from the repository the catalogue already builds that module
+// from**; and a module new to the catalogue only from a repository the catalogue already builds another
+// module from — whose trunk takes a reviewed, approved merge, which is how a merge adds a module (novox/hq
+// issue 300). Anything else — a module moved to another repository, a module from a repository the
+// catalogue has never built — is the operator's, at the controller's terminal: allowed only when the build
+// request was kept as asked there. Judged at the take-in, which every outcome reaches whoever hears it and
+// whichever verb asked it (`build`, `rebuild`, `replay --register`, `assign` with build), and before the ask
+// for a call through a verb, so an agent cannot have a build node run a repository the catalogue does not
+// build from at all.
+
+// errNotItsSource is an outcome refused for where it was built from.
+var errNotItsSource = errors.New("not built from the repository the catalogue builds it from")
+
+// servedVar marks every process the serving controller starts — each verb's command, each child — and the serving
+// process itself, so none of them can read as the operator at the terminal (novox/hq ADR 0266). Set by serve
+// before it answers anything, inherited by every child through os.Environ.
+const servedVar = "MESH_SERVED_BY_THE_CONTROLLER"
+
+// startedAtTheTerminal says this process was started at the controller's terminal: not the serving controller,
+// not anything it started, not a verb's command, not a seat call's. The serving controller marks its own
+// environment (servedVar), so a build asked in it, or by any process it starts, never reads as the terminal's;
+// runVerb also names the verb and the caller.
+//
+// **And a line mesh-cli asked as the controller's terminal** (novox/hq ADR 0272 §4): the serving controller runs it
+// without the served mark and without a verb, names its caller, and marks it with cliTerminalVar — a mark only the
+// mesh-cli path sets and every other command line the controller runs is stripped of (commandEnvironment).
+func startedAtTheTerminal() bool {
+	if os.Getenv(servedVar) != "" || os.Getenv(verbVar) != "" {
+		return false
+	}
+	return os.Getenv(link.CallerVar) == "" || os.Getenv(cliTerminalVar) != ""
+}
+
+// cliTerminalVar marks a command line the serving controller runs as the controller's terminal for mesh-cli.
+const cliTerminalVar = "MESH_CLI_TERMINAL"
+
+// markServed marks this process, and so everything it starts, as the serving controller's.
+func markServed() {
+	if err := os.Setenv(servedVar, "1"); err != nil {
+		panic("the serving controller could not mark its environment: " + err.Error())
+	}
+}
+
+// sourceForms compares sources however each is spelled: a path on a seat's holder (ADR 0111) or a URL — a
+// build asked of a seat's path is registered with the URL composed from it when its outcome does not echo
+// the seat. A seat's path is composed into its URL where the seat's holder is known, so both spellings of
+// one repository are one; where it is not, a seat's path matches only the same seat's same path.
+type sourceForms struct {
+	bases map[string]string // the seat's clone base, `scheme://host:port`, by seat; "" where it is not known
+	base  func(seat string) string
+}
+
+// newSourceForms reads the seats' bases from the mesh once, when first needed.
+func newSourceForms(ctx context.Context, inv *inventory.Inventory) *sourceForms {
+	f := &sourceForms{bases: map[string]string{}}
+	var world *catalogue.World
+	f.base = func(seat string) string {
+		if b, known := f.bases[seat]; known {
+			return b
+		}
+		if world == nil {
+			w := catalogue.World{}
+			if shelf, err := inv.Catalogue(ctx); err == nil {
+				if read, err := theRestOfTheMesh(ctx, inv, shelf, ""); err == nil {
+					w = read
+				}
+			}
+			world = &w
+		}
+		b, err := seatBase(*world, seat)
+		if err != nil {
+			b = ""
+		}
+		f.bases[seat] = b
+		return b
+	}
+	return f
+}
+
+// canonical is one spelling of a repository: lower case, no `.git`, no trailing slash, and a seat's path as
+// the URL its holder serves it at where that is known.
+func (f *sourceForms) canonical(repository, seat string) string {
+	trim := func(s string) string {
+		s = strings.TrimSpace(strings.ToLower(s))
+		s = strings.TrimRight(s, "/")
+		return strings.TrimRight(strings.TrimSuffix(s, ".git"), "/")
+	}
+	if seat == "" {
+		return trim(repository)
+	}
+	if b := f.base(seat); b != "" {
+		return trim(b + "/" + strings.Trim(repository, "/"))
+	}
+	return "seat:" + seat + ":" + trim(strings.Trim(repository, "/"))
+}
+
+// same says two sources are one repository.
+func (f *sourceForms) same(aRepository, aSeat, bRepository, bSeat string) bool {
+	if aRepository == "" || bRepository == "" {
+		return false
+	}
+	return f.canonical(aRepository, aSeat) == f.canonical(bRepository, bSeat)
+}
+
+// buildsFrom says the catalogue builds some module from this repository.
+func (f *sourceForms) buildsFrom(entries []inventory.Entry, repository, seat string) bool {
+	for _, e := range entries {
+		if e.Provided || e.Source.Repository == "" {
+			continue
+		}
+		if f.same(e.Source.Repository, e.Source.Seat, repository, seat) {
+			return true
+		}
+	}
+	return false
+}
+
+// forgeFacts is what the mesh's forge says of a repository a module is registered from (novox/hq ADR 0266).
+type forgeFacts struct {
+	// ID is the forge's own id of the repository: what tells it from one deleted and made again by its name.
+	ID int64
+	// Guarded is whether the branch is protected as a module's trunk must be: no direct push, at least one
+	// required status, and no administrator merging past one. Why says what is missing when it is not.
+	Guarded bool
+	Why     string
+}
+
+// askTheForge asks the forge, through its module's tools on the bus, for a repository's id and its branch's
+// protection, waiting out a forge not served for a moment (novox/hq issue 486). A variable so a test needs no
+// forge.
+var askTheForge = func(ctx context.Context, owner, repo, branch string) (forgeFacts, error) {
+	return forgeWaitedOut(ctx, forgeWait, owner+"/"+repo, func(ctx context.Context) (forgeFacts, error) {
+		return askTheForgeOnce(ctx, owner, repo, branch)
+	})
+}
+
+// waitOut bounds how long a question is asked again while its answer is "not now": a pause of first, doubling
+// to most, for at most bound in all. now and sleep are the clock, so a test waits in no real time.
+type waitOut struct {
+	bound, first, most time.Duration
+	now                func() time.Time
+	sleep              func(context.Context, time.Duration) error
+}
+
+// forgeWait is the registration's wait for the forge (novox/hq issue 486). On 2026-10-11 a build's registration
+// asked the forge while node-tools on the control-node re-served after a rollout of the tool runner, heard
+// "nothing serves gitea.gitea_api", and failed its plan; the forge answered again seconds later. A re-serve takes
+// about 10 s, so 60 s waits one out with room to spare. It is a cap on the whole wait, an ask in flight included:
+// the registration holds the controller's one receive loop while it waits, and a loop held two minutes reads as
+// deaf. The pauses are those the build machine waits the registry with (novox/hq issue 457).
+var forgeWait = waitOut{bound: 60 * time.Second, first: time.Second, most: 10 * time.Second,
+	now: time.Now, sleep: sleepOrDone}
+
+// sleepOrDone pauses for d, or less when ctx ends first.
+func sleepOrDone(ctx context.Context, d time.Duration) error {
+	t := time.NewTimer(d)
+	defer t.Stop()
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	case <-t.C:
+		return nil
+	}
+}
+
+// forgeNotNow is an answer that says the forge's tool is not served now — the tool runner re-serving — not that
+// the forge refused. Only that is asked again: a refusal, an unreadable answer or a repository with no id is the
+// forge's word, and a tool that did not answer in time has already held the receive loop its whole wait.
+func forgeNotNow(err error) bool { return errors.Is(err, link.ErrNothingServes) }
+
+// forgeWaitedOut asks the forge about repository, asking again while it answers "not served now", all of it
+// within w's bound, an ask in flight included (novox/hq issue 486). Past the bound it fails, saying it waited,
+// for how long, and what the forge last said; when the caller's own context ends, it says that instead.
+func forgeWaitedOut(ctx context.Context, w waitOut, repository string,
+	ask func(context.Context) (forgeFacts, error)) (forgeFacts, error) {
+	capped, cancel := context.WithTimeout(ctx, w.bound)
+	defer cancel()
+	began := w.now()
+	pause := w.first
+	for asked := 1; ; asked++ {
+		facts, err := ask(capped)
+		if err == nil {
+			if asked > 1 {
+				fmt.Printf("the forge answered about %s again, after %s (novox/hq issue 486)\n", repository,
+					w.now().Sub(began).Round(time.Second))
+			}
+			return facts, nil
+		}
+		if ctx.Err() != nil {
+			return forgeFacts{}, err // the caller's own context ended: no wait of ours to speak of
+		}
+		gaveUp := func() (forgeFacts, error) {
+			return forgeFacts{}, fmt.Errorf("waited %s for the forge to answer about %s, asking %d times, and it "+
+				"did not (novox/hq issue 486): %w", w.now().Sub(began).Round(time.Second), repository, asked, err)
+		}
+		if capped.Err() != nil {
+			return gaveUp() // the bound ended an ask in flight
+		}
+		if !forgeNotNow(err) {
+			return forgeFacts{}, err
+		}
+		if w.now().Sub(began)+pause > w.bound {
+			return gaveUp()
+		}
+		fmt.Printf("the forge cannot be asked about %s now (%v); asking again in %s, for at most %s in all "+
+			"(novox/hq issue 486)\n", repository, err, pause, w.bound)
+		if serr := w.sleep(capped, pause); serr != nil {
+			if ctx.Err() != nil {
+				return forgeFacts{}, fmt.Errorf("stopped waiting for the forge to answer about %s: %w", repository,
+					ctx.Err())
+			}
+			return gaveUp()
+		}
+		pause = min(2*pause, w.most)
+	}
+}
+
+// askTheForgeOnce asks the forge once, through its module's tools on the bus.
+func askTheForgeOnce(ctx context.Context, owner, repo, branch string) (forgeFacts, error) {
+	js, err := aBus()
+	if err != nil {
+		return forgeFacts{}, err
+	}
+	defer js.Close()
+	bus := link.OverNATS{Conn: js.Conn()}
+	ask := func(tool string, args map[string]any, into any) error {
+		raw, _ := json.Marshal(args)
+		answer, err := link.Ask(ctx, bus, "gitea", tool, raw, 30*time.Second)
+		if err != nil {
+			return err
+		}
+		if answer.Error != "" {
+			return fmt.Errorf("gitea.%s: %s", tool, answer.Error)
+		}
+		return json.Unmarshal(answer.Result, into)
+	}
+	var found struct {
+		Result struct {
+			ID       int64  `json:"id"`
+			FullName string `json:"full_name"`
+		} `json:"result"`
+	}
+	if err := ask("gitea_api", map[string]any{"path": "/repos/" + owner + "/" + repo}, &found); err != nil {
+		return forgeFacts{}, err
+	}
+	if found.Result.ID == 0 {
+		return forgeFacts{}, fmt.Errorf("the forge named no id for %s/%s", owner, repo)
+	}
+	var rules struct {
+		Rules []protectionRule `json:"rules"`
+	}
+	if err := ask("gitea_branch_protection_get", map[string]any{"owner": owner, "repo": repo}, &rules); err != nil {
+		return forgeFacts{}, err
+	}
+	facts := judgedRule(rules.Rules, branch)
+	facts.ID = found.Result.ID
+	return facts, nil
+}
+
+// protectionRule is a branch protection rule as the forge's tool summarises it.
+type protectionRule struct {
+	Rule             string   `json:"rule"`
+	Push             bool     `json:"push"`
+	RequiredStatuses []string `json:"required_statuses"`
+	AdminMayOverride bool     `json:"admin_may_override"`
+}
+
+// judgedRule judges the one rule the forge applies to a branch, as the forge picks it: the rule named for the
+// branch, else the first glob rule, in the forge's order, that covers it (gitea's first matching rule). Never a
+// later rule that happens to be stronger: the forge does not read it.
+func judgedRule(rules []protectionRule, branch string) forgeFacts {
+	var applied *protectionRule
+	for i := range rules {
+		if rules[i].Rule == branch {
+			applied = &rules[i]
+			break
+		}
+	}
+	if applied == nil {
+		for i := range rules {
+			if ruleCovers(rules[i].Rule, branch) {
+				applied = &rules[i]
+				break
+			}
+		}
+	}
+	switch r := applied; {
+	case r == nil:
+		return forgeFacts{Why: fmt.Sprintf("no protection rule covers %s", branch)}
+	case r.Push:
+		return forgeFacts{Why: fmt.Sprintf("the rule %s lets a person push to %s directly", r.Rule, branch)}
+	case len(r.RequiredStatuses) == 0:
+		return forgeFacts{Why: fmt.Sprintf("the rule %s requires no status before a merge into %s", r.Rule, branch)}
+	case r.AdminMayOverride:
+		return forgeFacts{Why: fmt.Sprintf("the rule %s lets an administrator merge into %s past a status", r.Rule, branch)}
+	}
+	return forgeFacts{Guarded: true}
+}
+
+// ruleCovers says a protection rule's name — a branch, or a glob of them — covers a branch, as the forge reads it.
+func ruleCovers(rule, branch string) bool {
+	if rule == branch {
+		return true
+	}
+	if !strings.ContainsAny(rule, "*?[") {
+		return false
+	}
+	var re strings.Builder
+	re.WriteString("^")
+	for i := 0; i < len(rule); i++ {
+		switch c := rule[i]; {
+		case c == '*' && i+1 < len(rule) && rule[i+1] == '*':
+			re.WriteString(".*")
+			i++
+		case c == '*':
+			re.WriteString("[^/]*")
+		case c == '?':
+			re.WriteString("[^/]")
+		default:
+			re.WriteString(regexp.QuoteMeta(string(c)))
+		}
+	}
+	re.WriteString("$")
+	ok, _ := regexp.MatchString(re.String(), branch)
+	return ok
+}
+
+// onTheForge is a source's owner and name on the mesh's own forge (the git seat's holder), and whether it is
+// there at all.
+func (f *sourceForms) onTheForge(repository, seat string) (owner, name string, ok bool) {
+	var rest string
+	switch {
+	case seat == gitSeat:
+		rest = strings.Trim(repository, "/")
+	case seat == "":
+		base := f.base(gitSeat)
+		if base == "" {
+			return "", "", false
+		}
+		url, prefix := f.canonical(repository, ""), f.canonical(base, "")+"/"
+		if !strings.HasPrefix(url, prefix) {
+			return "", "", false
+		}
+		// The case the forge spells it with: the URL as given, past the base.
+		rest = strings.TrimSuffix(strings.Trim(repository[len(prefix):], "/"), ".git")
+	default:
+		return "", "", false
+	}
+	parts := strings.Split(rest, "/")
+	if len(parts) != 2 || parts[0] == "" || parts[1] == "" {
+		return "", "", false
+	}
+	return parts[0], parts[1], true
+}
+
+// mayRegisterFrom says whether a build's outcome may register module from the source it was built from, and the
+// forge's id of that repository to record (novox/hq ADR 0266). Through any verb, only:
+//
+//   - from the module's registered repository — the same repository by the forge's own id, not only its name; or,
+//     for a module new to the catalogue, from a repository the catalogue builds another module from;
+//   - and from a repository on the mesh's forge whose trunk is protected as a trunk must be: no direct push, at
+//     least one required status, no administrator merging past one.
+//
+// Anything else only when the build request was kept as asked at the controller's terminal, for this very
+// repository and path; or, for the build of a merge, when mesh-delivery announced it on the operator's Approve of
+// that head (novox/hq ADR 0420 §7 for a moved module, ADR 0432 for a new one), the forge's checks still holding. path is the module's directory as built; branch the trunk it is registered from.
+func mayRegisterFrom(ctx context.Context, inv *inventory.Inventory, module string, built inventory.Source,
+	buildID, path, branch string) (int64, error) {
+	return mayRegisterIn(ctx, inv, newSourceForms(ctx, inv), module, built, buildID, path, branch)
+}
+
+// catalogueReader is the catalogue's manifests, as the router's records are found in them.
+type catalogueReader interface {
+	Catalogue(ctx context.Context) (map[string]catalogue.Manifest, error)
+}
+
+// registrations is what a registration's decision reads of the mesh: *inventory.Inventory, or a test's stand-in.
+type registrations interface {
+	catalogueReader
+	SourceOf(ctx context.Context, module string) (inventory.Source, error)
+	SourceIdentity(ctx context.Context, module string) (int64, error)
+	Catalogued(ctx context.Context) ([]inventory.Entry, error)
+	BuildRequestByID(ctx context.Context, id string) (inventory.BuildRequest, bool, error)
+	MergeOf(ctx context.Context, repository, commit string) (inventory.BatchedMerge, bool, error)
+}
+
+// mayRegisterIn is mayRegisterFrom on what it reads of the mesh handed in.
+func mayRegisterIn(ctx context.Context, inv registrations, forms *sourceForms, module string, built inventory.Source,
+	buildID, path, branch string) (int64, error) {
+	was, err := inv.SourceOf(ctx, module)
+	isNew := errors.Is(err, inventory.ErrNoSuchModule)
+	if err != nil && !isNew {
+		return 0, err
+	}
+	terminal, err := askedHereFor(ctx, inv, forms, buildID, built, path)
+	if err != nil {
+		return 0, err
+	}
+	refuse := func(why string) (int64, error) {
+		return 0, fmt.Errorf("%w: %s. A module is registered from such a source only by a build asked at the "+
+			"controller's terminal, or by the build of a merge mesh-delivery announced on the operator's Approve of that "+
+			"head, never through a verb: a registered module is what the next push sends, and whoever "+
+			"may call a verb includes agents (novox/hq ADR 0266)", errNotItsSource, why)
+	}
+
+	var why string
+	var alongside []inventory.Entry // the modules a new one's repository already builds
+	switch {
+	case !isNew && forms.same(was.Repository, was.Seat, built.Repository, built.Seat):
+	case !isNew:
+		registered := was.Repository
+		if registered == "" {
+			registered = "no repository (it was handed over by hand)"
+		}
+		why = fmt.Sprintf("%s is built from %s, and this build is of %s", module, sourceWords(registered, was.Seat),
+			sourceWords(built.Repository, built.Seat))
+	default:
+		entries, err := inv.Catalogued(ctx)
+		if err != nil {
+			return 0, err
+		}
+		for _, e := range entries {
+			if !e.Provided && e.Source.Repository != "" &&
+				forms.same(e.Source.Repository, e.Source.Seat, built.Repository, built.Seat) {
+				alongside = append(alongside, e)
+			}
+		}
+		if len(alongside) == 0 {
+			why = fmt.Sprintf("%s is new to the catalogue, and %s is no repository the catalogue builds a module from",
+				module, sourceWords(built.Repository, built.Seat))
+		}
+	}
+	// **Or the move the operator approved** (novox/hq ADR 0420 §7, issue 1025): a known module built from another
+	// repository by a merge, whose pull request mesh-delivery merged on the operator's Approve of that head.
+	// A verb alone, or a merge with no such warrant, is refused as before.
+	// **Or a new module from a repository nothing registered is built from, on the same warrant** (novox/hq ADR 0432,
+	// issue 1146): the build of a merge mesh-delivery announced on the operator's Approve of that head registers it.
+	// The forge's protection and the repository's identity are checked below as for every registration.
+	movedWhy := ""
+	if why != "" && !terminal {
+		accepted, err := approvedMove(ctx, inv, forms, buildID, built)
+		switch {
+		case err == nil:
+			movedWhy, why = accepted, ""
+		case !errors.Is(err, errNotAMerge):
+			fmt.Printf("%s: %s is built from another repository, and no approved move covers this build: %v\n",
+				buildID, module, err)
+		}
+	}
+	if why != "" && !terminal {
+		return refuse(why)
+	}
+
+	owner, name, onForge := forms.onTheForge(built.Repository, built.Seat)
+	if !onForge {
+		if terminal {
+			fmt.Printf("%s: %s is not on the mesh's forge — registered, as asked at the controller's terminal\n",
+				buildID, sourceWords(built.Repository, built.Seat))
+			return 0, nil
+		}
+		return refuse(fmt.Sprintf("%s is not on the mesh's forge, so whether its trunk is protected cannot be read",
+			sourceWords(built.Repository, built.Seat)))
+	}
+	facts, err := askTheForge(ctx, owner, name, branch)
+	if err != nil {
+		if terminal {
+			fmt.Printf("%s: the forge could not be asked about %s/%s (%v) — registered, as asked at the controller's "+
+				"terminal\n", buildID, owner, name, err)
+			return 0, nil
+		}
+		return refuse(fmt.Sprintf("the forge could not say whether %s/%s's %s is protected: %v", owner, name, branch, err))
+	}
+	if terminal {
+		if why != "" || !facts.Guarded {
+			fmt.Printf("%s: %s — registered, as asked at the controller's terminal\n", buildID,
+				strings.Trim(why+"; "+facts.Why, "; "))
+		}
+		return facts.ID, nil
+	}
+	if !facts.Guarded {
+		return refuse(fmt.Sprintf("%s/%s's %s is not protected as a module's trunk must be: %s", owner, name, branch,
+			facts.Why))
+	}
+	// The same repository by the forge's id, not only its name: one deleted and made again is another.
+	recorded := map[string]int64{}
+	// A moved module is registered from the repository the operator approved, not the one it was registered from.
+	if !isNew && movedWhy == "" {
+		id, err := inv.SourceIdentity(ctx, module)
+		if err != nil {
+			return 0, err
+		}
+		recorded[module] = id
+	}
+	for _, e := range alongside {
+		id, err := inv.SourceIdentity(ctx, e.Manifest.Module)
+		if err != nil {
+			return 0, err
+		}
+		recorded[e.Manifest.Module] = id
+	}
+	for m, id := range recorded {
+		if id != 0 && id != facts.ID {
+			return refuse(fmt.Sprintf("%s/%s is not the repository %s was registered from: the forge knows it as "+
+				"repository %d, and %s was registered from repository %d — one of that name deleted and made again",
+				owner, name, m, facts.ID, m, id))
+		}
+	}
+	if movedWhy != "" && isNew {
+		fmt.Printf("%s: %s is new, from %s/%s — registered at the operator's Approve: %s\n", buildID, module, owner, name,
+			movedWhy)
+	} else if movedWhy != "" {
+		fmt.Printf("%s: %s moved from %s to %s/%s — registered at the operator's Approve: %s\n", buildID, module,
+			sourceWords(was.Repository, was.Seat), owner, name, movedWhy)
+	}
+	return facts.ID, nil
+}
+
+// askedHereFor says the build was asked at the controller's terminal, for this repository and this path: a kept
+// request marked so, whose source is the outcome's (novox/hq ADR 0266).
+func askedHereFor(ctx context.Context, inv registrations, forms *sourceForms, buildID string,
+	built inventory.Source, path string) (bool, error) {
+	r, found, err := inv.BuildRequestByID(ctx, buildID)
+	if err != nil || !found || !r.AtTerminal {
+		return false, err
+	}
+	if !forms.same(r.Repository, r.Seat, built.Repository, built.Seat) ||
+		strings.Trim(r.Path, "/") != strings.Trim(path, "/") {
+		fmt.Printf("%s was asked at the terminal of %s at %q, and its outcome is of %s at %q: not the terminal's\n",
+			buildID, sourceWords(r.Repository, r.Seat), r.Path, sourceWords(built.Repository, built.Seat), path)
+		return false, nil
+	}
+	return true, nil
+}
+
+// sourceWords is a source as a person reads it.
+func sourceWords(repository, seat string) string {
+	if seat == "" {
+		return repository
+	}
+	return buildSource{Repository: repository, Seat: seat}.String()
+}
+
+// verbMayAsk refuses, for a call through a verb, a build of a repository the catalogue builds no module from
+// (novox/hq ADR 0266): the build node would run what an agent wrote, and its outcome could never be
+// registered anyway. url is the repository as it is cloned. At the terminal anything may be asked.
+func verbMayAsk(ctx context.Context, source buildSource, url string) error {
+	if startedAtTheTerminal() {
+		return nil
+	}
+	open, err := openStores(ctx)
+	if err != nil {
+		return err
+	}
+	defer open.Close()
+	entries, err := open.inventory.Catalogued(ctx)
+	if err != nil {
+		return err
+	}
+	forms := newSourceForms(ctx, open.inventory)
+	if forms.buildsFrom(entries, source.Repository, source.Seat) || forms.buildsFrom(entries, url, "") {
+		return nil
+	}
+	return terminalRefusal("%s is no repository the catalogue builds a module from, and a build of any other is "+
+		"asked at the controller's terminal only, never through a verb: a build node runs what the repository "+
+		"says, and its outcome would register a module the next push sends — whoever may call a verb includes "+
+		"agents (novox/hq ADR 0266). Nothing was asked", source)
+}

cmd/mesh-controller/build_source_integration_test.go

@@ -0,0 +1,353 @@
+//go:build integration
+
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"os"
+	"os/exec"
+	"slices"
+	"strings"
+	"testing"
+	"time"
+
+	"git.novox.be/novox/mesh-sdk/go/asks"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+func theCatalogue(t *testing.T) *stores {
+	t.Helper()
+	open := aMesh(t)
+	ctx := t.Context()
+	for _, b := range []link.BuildResult{
+		onTrunk("build-sudo", "novox/mesh-catalog", "git", "modules/sudo", map[string]any{"module": "sudo", "version": "1"}),
+		onTrunk("build-host", "novox/mesh-host", "git", "", map[string]any{"module": "mesh-host", "version": "1"}),
+	} {
+		keptAsked(t, open.inventory, b.ID, b.Source.Repository, b.Path, true)
+		if _, _, err := takeIn(ctx, open.inventory, b); err != nil {
+			t.Fatal(err)
+		}
+	}
+	return open
+}
+
+func TestABuildFromAnAgentsRepositoryIsNotRegisteredAsAModuleTheMeshHolds(t *testing.T) {
+	open := theCatalogue(t)
+	ctx := t.Context()
+	for _, c := range []struct {
+		name, repository, path, module string
+	}{
+		{"its own repository naming sudo", "agent/sudo", "modules/sudo", "sudo"},
+		{"a fork of the catalogue", "agent/mesh-catalog", "modules/sudo", "sudo"},
+		{"a fork of the node-engine", "agent/mesh-host", "", "mesh-host"},
+	} {
+		t.Run(c.name, func(t *testing.T) {
+			id := "build-" + strings.ReplaceAll(c.repository, "/", "-")
+			keptAsked(t, open.inventory, id, c.repository, c.path, false) // through the build verb
+			evil := onTrunk(id, c.repository, "git", c.path, map[string]any{"module": c.module, "version": "evil"})
+			_, _, err := takeIn(ctx, open.inventory, evil)
+			if !errors.Is(err, errNotItsSource) {
+				t.Fatalf("a build of %s was taken in as %s: %v", c.repository, c.module, err)
+			}
+			shelf, err := open.inventory.Catalogue(ctx)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if got := shelf[c.module].Version; got != "1" {
+				t.Fatalf("%s is now %q, from %s", c.module, got, c.repository)
+			}
+			if _, found, _ := open.inventory.BuildByID(ctx, id); !found {
+				t.Errorf("the refused build %s is not recorded", id)
+			}
+		})
+	}
+}
+
+func TestANewModuleFromARepositoryTheCatalogueDoesNotBuildFromIsNotRegistered(t *testing.T) {
+	open := theCatalogue(t)
+	ctx := t.Context()
+	keptAsked(t, open.inventory, "build-new", "agent/tools", "", false)
+	_, _, err := takeIn(ctx, open.inventory, onTrunk("build-new", "agent/tools", "git", "",
+		map[string]any{"module": "agent-tools", "version": "1"}))
+	if !errors.Is(err, errNotItsSource) {
+		t.Fatalf("a new module from an agent's repository was taken in: %v", err)
+	}
+	// And one asked of nobody here — an outcome on the bus no request was kept for — the same.
+	_, _, err = takeIn(ctx, open.inventory, onTrunk("build-unasked", "agent/tools", "git", "",
+		map[string]any{"module": "agent-tools", "version": "1"}))
+	if !errors.Is(err, errNotItsSource) {
+		t.Fatalf("an outcome nobody asked for was taken in: %v", err)
+	}
+	if shelf, _ := open.inventory.Catalogue(ctx); shelf["agent-tools"].Module != "" {
+		t.Fatal("the refused module is in the catalogue")
+	}
+}
+
+func TestAtTheTerminalAnotherRepositoryIsRegistered(t *testing.T) {
+	open := theCatalogue(t)
+	ctx := t.Context()
+	keptAsked(t, open.inventory, "build-moved", "novox/sudo", "", true)
+	if _, _, err := takeIn(ctx, open.inventory, onTrunk("build-moved", "novox/sudo", "git", "",
+		map[string]any{"module": "sudo", "version": "2"})); err != nil {
+		t.Fatalf("a move the operator asked for at the terminal was refused: %v", err)
+	}
+	if src, _ := open.inventory.SourceOf(ctx, "sudo"); src.Repository != "novox/sudo" {
+		t.Fatalf("sudo is built from %q", src.Repository)
+	}
+	if err := open.inventory.RecordBuildRequest(ctx, inventory.BuildRequest{ID: "build-external",
+		Repository: "http://forge.internal:20000/someone/app.git", For: "build", AtTerminal: true}); err != nil {
+		t.Fatal(err)
+	}
+	if _, _, err := takeIn(ctx, open.inventory, onTrunk("build-external", "someone/app", "", "",
+		map[string]any{"module": "app", "version": "1"})); err != nil {
+		t.Fatalf("a new module the operator asked for at the terminal was refused: %v", err)
+	}
+}
+
+func TestADeliveryFromTheRegisteredRepositoryIsRegistered(t *testing.T) {
+	open := theCatalogue(t)
+	ctx := t.Context()
+	rebuilt := onTrunk("build-plan", "novox/mesh-catalog", "git", "modules/sudo", map[string]any{"module": "sudo", "version": "2"})
+	if err := open.inventory.RecordBuildRequest(ctx, inventory.BuildRequest{ID: rebuilt.ID,
+		Repository: "novox/mesh-catalog", Seat: "git", Path: "modules/sudo", For: "plan"}); err != nil {
+		t.Fatal(err)
+	}
+	if _, _, err := takeIn(ctx, open.inventory, rebuilt); err != nil {
+		t.Fatalf("a plan's build of the module's own repository was refused: %v", err)
+	}
+	added := onTrunk("build-merge", "novox/mesh-catalog", "git", "modules/zram", map[string]any{"module": "zram", "version": "1"})
+	if _, _, err := takeIn(ctx, open.inventory, added); err != nil {
+		t.Fatalf("a module a merge added to the catalogue repository was refused: %v", err)
+	}
+	shelf, _ := open.inventory.Catalogue(ctx)
+	if shelf["sudo"].Version != "2" || shelf["zram"].Module == "" {
+		t.Fatalf("not registered: sudo %q, zram %q", shelf["sudo"].Version, shelf["zram"].Module)
+	}
+}
+
+func TestAVerbAsksNoBuildOfARepositoryTheCatalogueDoesNotBuildFrom(t *testing.T) {
+	theCatalogue(t)
+	ctx := t.Context()
+	t.Setenv(verbVar, "build")
+	t.Setenv(link.CallerVar, "node-tools.anchor, through the mesh-controller seat")
+	err := verbMayAsk(ctx, buildSource{Repository: "agent/sudo", Seat: "git"}, "http://forge.internal:20000/agent/sudo.git")
+	var policy *heldAtTheTerminal
+	if !errors.As(err, &policy) {
+		t.Fatalf("a verb's build of an agent's repository was asked: %v", err)
+	}
+	if err := verbMayAsk(ctx, buildSource{Repository: "novox/mesh-catalog", Seat: "git"},
+		"http://forge.internal:20000/novox/mesh-catalog.git"); err != nil {
+		t.Fatalf("a verb's build of the catalogue repository was refused: %v", err)
+	}
+	t.Setenv(verbVar, "")
+	t.Setenv(link.CallerVar, "")
+	if err := verbMayAsk(ctx, buildSource{Repository: "agent/sudo", Seat: "git"}, ""); err != nil {
+		t.Fatalf("the terminal was refused: %v", err)
+	}
+}
+
+func TestARollbackNeverPutsBackABuildFromAnotherRepository(t *testing.T) {
+	open := theCatalogue(t)
+	ctx := t.Context()
+	inv := open.inventory
+	fork := onTrunk("build-1791500000000000000", "agent/mesh-catalog", "git", "modules/sudo",
+		map[string]any{"module": "sudo", "version": "evil"})
+	fork.Commit = "c0ffee0123456789" // the commit sudo was registered at
+	keptAsked(t, inv, fork.ID, "agent/mesh-catalog", "modules/sudo", false)
+	if _, _, err := takeIn(ctx, inv, fork); !errors.Is(err, errNotItsSource) {
+		t.Fatalf("the fork's build was taken in: %v", err)
+	}
+	// Asked after the registered build, whenever the test runs: an id naming a fixed moment read as older
+	// than the registered build once the clock passed it (2026-10-10 02:40 UTC), and the test failed on main.
+	failed := onTrunk(fmt.Sprintf("build-%d", time.Now().Add(time.Hour).UnixNano()), "novox/mesh-catalog", "git", "modules/sudo",
+		map[string]any{"module": "sudo", "version": "2"})
+	failed.Commit = "badbadbad0123456"
+	if _, _, err := takeIn(ctx, inv, failed); err != nil {
+		t.Fatal(err)
+	}
+	record, _, err := inv.BuildByID(ctx, failed.ID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	previous, found, err := inv.PreviousBuild(ctx, "sudo", "c0ffee0123456789", record)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if found && previous.ID == fork.ID {
+		t.Fatalf("a rollback would put back the fork's build %s", previous.ID)
+	}
+	if !found || previous.ID != "build-sudo" {
+		t.Fatalf("a rollback puts back %q (found %v), want the registered build-sudo", previous.ID, found)
+	}
+}
+
+func TestATrunkTheForgeDoesNotProtectRegistersNothing(t *testing.T) {
+	open := theCatalogue(t)
+	ctx := t.Context()
+	theForge.Store("novox/unguarded", forgeFacts{ID: 7, Why: "the rule main lets a person push to main directly"})
+	t.Cleanup(func() { theForge.Delete("novox/unguarded") })
+	first := onTrunk("build-unguarded-1", "novox/unguarded", "git", "", map[string]any{"module": "unguarded", "version": "1"})
+	keptAsked(t, open.inventory, first.ID, "novox/unguarded", "", true)
+	if _, _, err := takeIn(ctx, open.inventory, first); err != nil {
+		t.Fatalf("at the terminal: %v", err)
+	}
+	again := onTrunk("build-unguarded-2", "novox/unguarded", "git", "", map[string]any{"module": "unguarded", "version": "2"})
+	if _, _, err := takeIn(ctx, open.inventory, again); !errors.Is(err, errNotItsSource) ||
+		!strings.Contains(err.Error(), "push to main directly") {
+		t.Fatalf("a rebuild from an unprotected trunk was taken in: %v", err)
+	}
+	theForge.Store("novox/unguarded", errors.New("nothing serves gitea.gitea_api"))
+	if _, _, err := takeIn(ctx, open.inventory, onTrunk("build-unguarded-3", "novox/unguarded", "git", "",
+		map[string]any{"module": "unguarded", "version": "3"})); !errors.Is(err, errNotItsSource) {
+		t.Fatalf("a forge that could not say was read as a protected trunk: %v", err)
+	}
+	if shelf, _ := open.inventory.Catalogue(ctx); shelf["unguarded"].Version != "1" {
+		t.Fatalf("unguarded is %q", shelf["unguarded"].Version)
+	}
+}
+
+func TestARepositoryMadeAgainUnderItsNameIsNotTheModulesSource(t *testing.T) {
+	open := theCatalogue(t)
+	ctx := t.Context()
+	theForge.Store("novox/remade", forgeFacts{ID: 100, Guarded: true})
+	t.Cleanup(func() { theForge.Delete("novox/remade") })
+	first := onTrunk("build-remade-1", "novox/remade", "git", "", map[string]any{"module": "remade", "version": "1"})
+	keptAsked(t, open.inventory, first.ID, "novox/remade", "", true)
+	if _, _, err := takeIn(ctx, open.inventory, first); err != nil {
+		t.Fatal(err)
+	}
+	if id, _ := open.inventory.SourceIdentity(ctx, "remade"); id != 100 {
+		t.Fatalf("the forge's id was not recorded: %d", id)
+	}
+	theForge.Store("novox/remade", forgeFacts{ID: 101, Guarded: true}) // deleted, and made again by an agent
+	if _, _, err := takeIn(ctx, open.inventory, onTrunk("build-remade-2", "novox/remade", "git", "",
+		map[string]any{"module": "remade", "version": "evil"})); !errors.Is(err, errNotItsSource) ||
+		!strings.Contains(err.Error(), "made again") {
+		t.Fatalf("a repository made again under the name was taken in: %v", err)
+	}
+	// And a new module from it, beside the one registered from the first, the same.
+	if _, _, err := takeIn(ctx, open.inventory, onTrunk("build-remade-3", "novox/remade", "git", "modules/other",
+		map[string]any{"module": "other", "version": "1"})); !errors.Is(err, errNotItsSource) {
+		t.Fatalf("a new module from a repository made again was taken in: %v", err)
+	}
+}
+
+func TestATerminalRequestCoversOnlyWhatItAsked(t *testing.T) {
+	open := theCatalogue(t)
+	ctx := t.Context()
+	if err := open.inventory.RecordBuildRequest(ctx, inventory.BuildRequest{ID: "build-asked", Repository: "novox/app",
+		Seat: "git", Path: "modules/app", For: "build", AtTerminal: true}); err != nil {
+		t.Fatal(err)
+	}
+	other := onTrunk("build-asked", "agent/sudo", "git", "modules/app", map[string]any{"module": "sudo", "version": "evil"})
+	if _, _, err := takeIn(ctx, open.inventory, other); !errors.Is(err, errNotItsSource) {
+		t.Fatalf("an outcome of another repository under a terminal request's id was taken in: %v", err)
+	}
+	elsewhere := onTrunk("build-asked", "novox/app", "git", "modules/sudo", map[string]any{"module": "sudo", "version": "evil"})
+	if _, _, err := takeIn(ctx, open.inventory, elsewhere); !errors.Is(err, errNotItsSource) {
+		t.Fatalf("an outcome of another path under a terminal request's id was taken in: %v", err)
+	}
+}
+
+func TestTheServingControllerIsNeverTheTerminal(t *testing.T) {
+	t.Setenv(verbVar, "")
+	t.Setenv(link.CallerVar, "")
+	t.Setenv(servedVar, "")
+	if !startedAtTheTerminal() {
+		t.Fatal("a process started by hand is not the terminal")
+	}
+	markServed()
+	if startedAtTheTerminal() {
+		t.Fatal("the serving controller reads as the terminal")
+	}
+	child := exec.Command(os.Args[0], "-test.run=^$")
+	child.Env = os.Environ()
+	if !slices.Contains(child.Env, servedVar+"=1") {
+		t.Fatal("what the serving controller starts does not carry its mark")
+	}
+}
+
+func TestAnUnknownIdentityKeepsTheRecordedOne(t *testing.T) {
+	open := theCatalogue(t)
+	ctx := t.Context()
+	if err := open.inventory.SetSourceIdentity(ctx, "sudo", 100); err != nil {
+		t.Fatal(err)
+	}
+	if err := open.inventory.SetSourceIdentity(ctx, "sudo", 0); err != nil {
+		t.Fatal(err)
+	}
+	if id, _ := open.inventory.SourceIdentity(ctx, "sudo"); id != 100 {
+		t.Fatalf("the recorded id became %d", id)
+	}
+}
+
+func TestAModuleMovesOnTheOperatorsApproveOfTheMergeThatMovedIt(t *testing.T) {
+	const commit = "c0ffee0123456789"
+	for _, c := range []struct {
+		what    string
+		change  func(*anApprovedMerge)
+		unkept  bool
+		request string // who asked: "merge", or "build" through a verb
+		moved   bool
+	}{
+		{what: "the operator's Approve of the merged head", request: "merge", moved: true},
+		{what: "no merge mesh-delivery announced", unkept: true, request: "merge"},
+		{what: "a warrant for other heads", request: "merge", change: func(a *anApprovedMerge) {
+			a.merge.Heads = map[string]string{"novox/mesh-host@aaaaaaaaaaaa": "e5e5e5e5e5e5e5e5e5e5e5e5e5e5e5e5e5e5e5e5"}
+		}},
+		{what: "a Decline", request: "merge", change: func(a *anApprovedMerge) {
+			a.warrant.Option, a.warrant.Label, a.merge.Option = "decline", "Decline", "decline"
+		}},
+		{what: "a person who is not the operator", request: "merge", change: func(a *anApprovedMerge) { a.warrant.By.Who = "agent" }},
+		{what: "a build asked through a verb", request: "build"},
+	} {
+		open := theCatalogue(t)
+		ctx := t.Context()
+		inv := open.inventory
+		a := approvedMerge(t)
+		a.merge.Owner, a.merge.Repo, a.merge.Number, a.merge.HeadSHA = "novox", "mesh-host", 7, "a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1a1"
+		if c.change != nil {
+			c.change(&a)
+		}
+		wasKept, wasAsk := keptDeliveryMerge, routerAskOf
+		keptDeliveryMerge = func(_ context.Context, owner, repo string, number int, head string) (deliveryMerge, bool, error) {
+			return a.merge, !c.unkept && owner == "novox" && repo == "mesh-host" && number == 7 && head == a.merge.HeadSHA, nil
+		}
+		routerAskOf = func(_ context.Context, _ catalogueReader, id string) (*asks.Ask, *asks.Warrant, error) {
+			if id != a.merge.AskID {
+				t.Errorf("%s: the router was asked for %q", c.what, id)
+			}
+			return &a.ask, &a.warrant, nil
+		}
+		t.Cleanup(func() { keptDeliveryMerge, routerAskOf = wasKept, wasAsk })
+		event, _ := json.Marshal(map[string]any{"owner": "novox", "repo": "mesh-host", "base": "main", "number": 7,
+			"head_sha": a.merge.HeadSHA, "merge_commit_sha": commit})
+		if _, err := inv.AddMerge(ctx, inventory.BatchedMerge{Repository: "novox/mesh-host", Branch: "main", Commit: commit,
+			Merged: time.Now(), Heard: time.Now(), Event: event}); err != nil {
+			t.Fatal(err)
+		}
+		id := fmt.Sprintf("build-%d", time.Now().Add(time.Hour).UnixNano())
+		if err := inv.RecordBuildRequest(ctx, inventory.BuildRequest{ID: id, Repository: "novox/mesh-host", Seat: "git",
+			Path: "modules/sudo", Ref: "main", Commit: commit, For: c.request}); err != nil {
+			t.Fatal(err)
+		}
+		moved := onTrunk(id, "novox/mesh-host", "git", "modules/sudo", map[string]any{"module": "sudo", "version": "2"})
+		moved.Commit = commit
+		_, _, err := takeIn(ctx, inv, moved)
+		src, _ := inv.SourceOf(ctx, "sudo")
+		switch {
+		case c.moved && err != nil:
+			t.Errorf("%s: the move was refused: %v", c.what, err)
+		case c.moved && src.Repository != "novox/mesh-host":
+			t.Errorf("%s: sudo is built from %q", c.what, src.Repository)
+		case !c.moved && !errors.Is(err, errNotItsSource):
+			t.Errorf("%s: the move was not refused as ADR 0266 has it: %v", c.what, err)
+		case !c.moved && src.Repository != "novox/mesh-catalog":
+			t.Errorf("%s: a refused move changed sudo's source to %q", c.what, src.Repository)
+		}
+	}
+}

cmd/mesh-controller/build_source_test.go

@@ -0,0 +1,128 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"hash/fnv"
+	"strings"
+	"sync"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// The routes to root a review of ADR 0266 found (novox/hq ADR 0266 §7): an agent makes a repository of its
+// own — or forks one the mesh builds from — commits a module.json naming a module the mesh runs everywhere
+// (`sudo`, granting itself a rule without a password; `mesh-host`, the node-engine), and asks the `build` verb
+// for it. Its outcome was registered under that name from the agent's repository, and the next push sent it.
+
+// onTrunk is an outcome of a commit on its repository's trunk, as the build seat says it.
+func onTrunk(id, repository, seat, path string, manifest map[string]any) link.BuildResult {
+	raw, _ := json.Marshal(manifest)
+	r := link.BuildResult{ID: id, Repository: "http://forge.internal:20000/" + repository + ".git", Path: path,
+		Ref: "main", On: "anchor", Commit: "c0ffee0123456789", Manifest: raw,
+		Trunk: "main", OnTrunk: true, Branches: []string{"main"}}
+	if seat != "" {
+		r.Source = &link.SourceOnSeat{Seat: seat, Repository: repository}
+	}
+	return r
+}
+
+// keptAsked keeps a build request as the asker would: through a verb, or at the terminal.
+func keptAsked(t *testing.T, inv *inventory.Inventory, id, repository, path string, atTerminal bool) {
+	t.Helper()
+	if err := inv.RecordBuildRequest(t.Context(), inventory.BuildRequest{ID: id, Repository: repository, Seat: "git",
+		Path: path, For: "build", AtTerminal: atTerminal}); err != nil {
+		t.Fatal(err)
+	}
+}
+
+// theCatalogue is a mesh whose sudo is built from the catalogue repository and whose node-engine from its own.
+
+// The operator at the terminal may still move a module, or add one from a new repository.
+
+// The delivery's flow is untouched: a merge's rebuild of a module from its own repository, and a merge adding
+// a module to a repository the catalogue builds from (novox/hq issue 300), are registered with no terminal.
+
+// Through a verb, a build of a repository the catalogue builds nothing from is not even asked: the build node
+// would run what the agent wrote.
+
+// asTheOperator keeps a build as asked at the controller's terminal, as the operator's first build of a module
+// from a repository the catalogue does not yet build from is (novox/hq ADR 0266), and hands it back.
+func asTheOperator(t *testing.T, inv *inventory.Inventory, b link.BuildResult) link.BuildResult {
+	t.Helper()
+	repository, seat := b.Repository, ""
+	if b.Source != nil {
+		repository, seat = b.Source.Repository, b.Source.Seat
+	}
+	if err := inv.RecordBuildRequest(t.Context(), inventory.BuildRequest{ID: b.ID, Repository: repository, Seat: seat,
+		Path: b.Path, For: "build", AtTerminal: true}); err != nil {
+		t.Fatal(err)
+	}
+	return b
+}
+
+// A rollback puts back only a build of the module's own repository: an agent's build of the module's name,
+// recorded and refused, at the very commit the machine ran before (a fork carries it), is never registered by
+// the back door of a failed gate.
+
+// theForge is what the forge says in a test, by owner/name: a repository not named here is protected as a
+// trunk must be, with an id of its own.
+var theForge sync.Map
+
+func init() {
+	askTheForge = func(_ context.Context, owner, repo, _ string) (forgeFacts, error) {
+		if said, ok := theForge.Load(owner + "/" + repo); ok {
+			switch f := said.(type) {
+			case error:
+				return forgeFacts{}, f
+			case forgeFacts:
+				return f, nil
+			}
+		}
+		h := fnv.New32a()
+		_, _ = h.Write([]byte(owner + "/" + repo))
+		return forgeFacts{ID: int64(h.Sum32()), Guarded: true}, nil
+	}
+}
+
+// A module's trunk the forge does not protect — direct pushes, no required status — or a forge that cannot say,
+// registers nothing through a verb: the trunk rule means nothing on a branch anyone pushes to.
+
+// A repository deleted and made again under the module's repository's name is another repository: the forge's
+// id, recorded at registration, tells them apart.
+
+// The terminal's mark is the operator's for the repository and path they asked: an outcome of another, under that
+// build's id, is not theirs.
+
+// The serving controller, and everything it starts, is never the terminal: a build asked in it reads as asked
+// through the mesh even when no verb and no caller is named.
+
+// The forge applies one rule to a branch: the rule named for it, else the first glob that covers it. A stronger
+// rule later in the list is not what guards the branch, and is not read as if it were (the confirmation review).
+func TestTheRuleJudgedIsTheOneTheForgeApplies(t *testing.T) {
+	guarded := protectionRule{Rule: "*", RequiredStatuses: []string{"mesh/merge-gate"}}
+	open := protectionRule{Rule: "main", Push: true, RequiredStatuses: []string{"mesh/merge-gate"}}
+	if f := judgedRule([]protectionRule{guarded, open}, "main"); f.Guarded {
+		t.Error("an exact rule letting pushes was passed over for a glob that guards")
+	}
+	if f := judgedRule([]protectionRule{{Rule: "ma*", RequiredStatuses: nil}, {Rule: "*", RequiredStatuses: []string{"x"}}},
+		"main"); f.Guarded || !strings.Contains(f.Why, "ma*") {
+		t.Errorf("the first glob covering the branch was not the one judged: %+v", f)
+	}
+	if f := judgedRule([]protectionRule{{Rule: "release/*"}, {Rule: "main", RequiredStatuses: []string{"x"}}}, "main"); !f.Guarded {
+		t.Errorf("the rule named for the branch was not judged: %+v", f)
+	}
+	if f := judgedRule(nil, "main"); f.Guarded {
+		t.Error("no rule is no protection")
+	}
+}
+
+// An id the forge could not give keeps the id already recorded.
+
+// **The operator's Approve of a reviewed group registers a moved module from its new repository** (novox/hq ADR 0420 §7,
+// issue 1025). sudo is built from the catalogue; a merge into the repository of node-engine's module, announced by
+// mesh-delivery with the ask it merged on, brings its build from there. Accepted with the operator's Approve of the
+// merged head; refused with no kept merge, a warrant for other heads, a Decline, a person who is not the operator, and
+// through a verb.

cmd/mesh-controller/build_test.go

@@ -0,0 +1,34 @@
+package main
+
+import (
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// A build's outcome is taken in the same way whoever hears it (novox/hq issue 176): recorded, and
+// the module registered with its source as the seat and path when the request said so — never the
+// URL. A definition naming an installation is recorded and not registered; a failure is recorded
+// and said.
+
+// novox/hq 04-ISSUES/215: a build asked at a commit is recorded as built from that commit, and the
+// module keeps following the branch it followed — a new one, the default branch.
+
+// novox/hq 04-ISSUES/219: an older request heard after a newer one is recorded and not registered,
+// so a push sends what the newer request built.
+
+func TestABuildIDSaysWhenItWasAsked(t *testing.T) {
+	at := time.Date(2026, 10, 3, 21, 51, 57, 392539762, time.UTC)
+	if got, ok := link.BuildAskedAt(link.NewBuildID(at)); !ok || !got.Equal(at) {
+		t.Errorf("read back %v %v; want %v", got, ok, at)
+	}
+	if got, ok := link.BuildAskedAt("build-1791064317392539762"); !ok || got.Format(time.TimeOnly) != "21:51:57" {
+		t.Errorf("the incident's id reads as %v %v", got, ok)
+	}
+	for _, id := range []string{"b-1", "build-2", "build-", "build-x", ""} {
+		if _, ok := link.BuildAskedAt(id); ok {
+			t.Errorf("%q read as a request time", id)
+		}
+	}
+}

cmd/mesh-controller/bus_step.go

@@ -0,0 +1,410 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"flag"
+	"fmt"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/nats-io/nats.go"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// The bus as a planned step (novox/hq to-be 45 §8, ADR 0227 rule 8, ADR 0236).
+//
+// **A bus upgrade is never rolled out.** The bus carries every declaration, every report and the
+// controller's own lease; a new bus build that does not come up is a mesh nobody can tell anything,
+// and a version whose data format moved (2.10 → 2.11) cannot be undone by putting the old one back.
+// So nothing sends a new bus build on its own: its policy is `record` whatever anyone says (the
+// catalogue's DerivedUpgrade, and `upgrade` refuses a roll-out), a plan builds it and sends nothing, a
+// cascade holds the machine (ADR 0221), and a push naming that machine is refused while a new bus build
+// waits for it (busHeld). The one way is this verb: a person, with why, the streams snapshotted first,
+// whether it can be reverted said before it starts, the step said as `bus-maintenance` while it runs,
+// and every stream, durable consumer and a round trip checked after (H-bus) — or the step said failed,
+// with its snapshot as the way back.
+
+// busStepProbe is the registry's row for the step; its kinds.
+const (
+	busStepProbe         = "DB"
+	kindBusMaintenance   = "bus-maintenance"
+	kindBusUpgradeFailed = "bus-upgrade-failed"
+)
+
+// busStepBound is how long after its start a bus upgrade must be followed by a healthy bus.
+var busStepBound = 15 * time.Minute
+
+// takeBusSnapshot snapshots every stream before a bus upgrade and answers where the snapshot is: the bus
+// machine's backup holder backs the bus module up now, whose dump is the streams' snapshot (novox/hq ADR
+// 0235). A variable so a test takes none. A person who took one by hand says where with --snapshot-taken,
+// and then none is taken — for a bus whose module does not yet carry the snapshot program.
+var takeBusSnapshot = snapshotTheBusNow
+
+// busPending is what a bus upgrade would do: the bus's module, the machines running it, and, per
+// machine, the build it was last sent against the build the mesh holds. Empty machines: the mesh holds
+// no bus module.
+type busPending struct {
+	module   string
+	machines []string
+	from     map[string]string
+	to       string
+	// same are the commits whose build was made from the same source as the build the mesh holds, or
+	// made the same artifacts and manifest (novox/hq issue 280).
+	same map[string]bool
+}
+
+// moves is whether sending the machine would replace its bus: a build it was not last sent, unless the
+// two builds were made from the same source, or made the same artifacts from the same manifest — a
+// rebuild of the same source for another module's merge changes nothing the machine runs, whatever
+// image digest it made (novox/hq issue 280).
+func (b busPending) moves(machine string) bool {
+	from, known := b.from[machine]
+	if b.module == "" || b.to == "" || (known && sameCommit(from, b.to)) {
+		return false
+	}
+	return !known || !b.same[from]
+}
+
+// pendingBus reads what a bus upgrade would do.
+func pendingBus(ctx context.Context, inv *inventory.Inventory) (busPending, error) {
+	var b busPending
+	shelf, err := inv.Catalogue(ctx)
+	if err != nil {
+		return b, err
+	}
+	for name, m := range shelf {
+		if catalogue.ProvidesBus(m) {
+			b.module = name
+		}
+	}
+	if b.module == "" {
+		return b, nil
+	}
+	current, err := inv.CurrentBuilds(ctx)
+	if err != nil {
+		return b, err
+	}
+	b.to = current[b.module].Commit
+	if b.machines, err = inv.Running(ctx, b.module); err != nil {
+		return b, err
+	}
+	b.from, b.same = map[string]string{}, map[string]bool{}
+	made, err := inv.BuildFingerprints(ctx, b.module)
+	if err != nil {
+		return b, err
+	}
+	for commit, refs := range made {
+		b.same[commit] = refs != "" && refs == made[b.to]
+	}
+	sources, err := inv.BuildSourceFingerprints(ctx, b.module)
+	if err != nil {
+		return b, err
+	}
+	for commit, src := range sources {
+		if src != "" && src == sources[b.to] {
+			b.same[commit] = true
+		}
+	}
+	for _, n := range b.machines {
+		sent, known, err := inv.SentBuilds(ctx, n)
+		if err != nil {
+			return b, err
+		}
+		if known {
+			if c, carried := sent[b.module]; carried {
+				b.from[n] = c
+			}
+		}
+	}
+	return b, nil
+}
+
+// busHeld names the machines a push may not send because sending them would replace the bus: the
+// planned step's, not a push's (ADR 0236). Said with the remedy.
+func busHeld(ctx context.Context, inv *inventory.Inventory, machines []string) (map[string]string, error) {
+	b, err := pendingBus(ctx, inv)
+	if err != nil {
+		return nil, err
+	}
+	out := map[string]string{}
+	for _, n := range machines {
+		for _, holder := range b.machines {
+			if n == holder && b.moves(n) {
+				out[n] = fmt.Sprintf("sending %s would replace the bus (%s %s → %s), which is a planned step: "+
+					"`bus upgrade --why …` snapshots its streams first and checks them after (novox/hq ADR 0236)",
+					n, b.module, short(orNotKnown(b.from[n])), short(b.to))
+			}
+		}
+	}
+	return out, nil
+}
+
+// busCommand is `bus` — what a bus upgrade would do and how the last went — and `bus upgrade`.
+func busCommand(ctx context.Context, args []string) error {
+	sub := ""
+	if len(args) > 0 && !strings.HasPrefix(args[0], "-") {
+		sub, args = args[0], args[1:]
+	}
+	set := flag.NewFlagSet("bus", flag.ContinueOnError)
+	snapshot := set.String("snapshot-taken", "", "where the streams' snapshot a person took is, while the mesh takes none itself")
+	reversible := set.Bool("reversible", false, "the new version can be undone by putting the old one back")
+	irreversible := set.Bool("irreversible", false, "the new version cannot be undone by putting the old one back, "+
+		"and this is the person's explicit word that it runs anyway")
+	why := addHandActFlags(set)
+	if rest, err := parseAround(set, args); err != nil {
+		return err
+	} else if len(rest) > 0 {
+		return errors.New("bus [upgrade --why … --reversible|--irreversible [--snapshot-taken <where>]]")
+	}
+	switch sub {
+	case "":
+		return busStatus(ctx)
+	case "upgrade":
+	default:
+		return fmt.Errorf("bus says what a bus upgrade would do, or `bus upgrade` — not %q", sub)
+	}
+	// Everything refused before anything is done.
+	if err := why.require("bus upgrade"); err != nil {
+		return err
+	}
+	if *reversible == *irreversible {
+		return errors.New("bus upgrade says, before it starts, whether the new version can be undone by putting the " +
+			"old one back: --reversible, or --irreversible as your explicit word that it runs anyway (to-be 45 §8). " +
+			"Nothing was done")
+	}
+	open, err := openStores(ctx)
+	if err != nil {
+		return err
+	}
+	defer open.Close()
+	inv := open.inventory
+	b, err := pendingBus(ctx, inv)
+	if err != nil {
+		return err
+	}
+	if b.module == "" {
+		return errors.New("the mesh holds no module that provides its bus: there is nothing to upgrade")
+	}
+	var moving []string
+	for _, n := range b.machines {
+		if b.moves(n) {
+			moving = append(moving, n)
+		}
+	}
+	if len(moving) == 0 {
+		fmt.Printf("every machine running %s runs the build the mesh holds (%s): nothing to upgrade\n", b.module, short(b.to))
+		return nil
+	}
+	where := strings.TrimSpace(*snapshot)
+	if where == "" {
+		for _, n := range moving {
+			fmt.Printf("snapshotting the bus's streams on %s first (its backup holder, ADR 0235)…\n", n)
+			if where, err = takeBusSnapshot(ctx, b.module, n); err != nil {
+				return fmt.Errorf("the streams could not be snapshotted, so the bus is not replaced: %w — a snapshot "+
+					"taken by hand is said with --snapshot-taken <where>", err)
+			}
+		}
+	}
+	from := map[string]bool{}
+	for _, n := range moving {
+		from[orNotKnown(b.from[n])] = true
+	}
+	step, err := inv.StartBusStep(ctx, inventory.BusStep{Module: b.module, Machines: moving,
+		From: strings.Join(sortedKeys(from), ", "), To: b.to, Snapshot: where, Reversible: *reversible,
+		By: link.Caller(), Why: strings.TrimSpace(*why.why)})
+	if err != nil {
+		return err
+	}
+	cause := "bus-upgrade"
+	if strings.TrimSpace(*why.cause) == "" {
+		why.cause = &cause
+	}
+	why.record(ctx, "bus upgrade", append([]string{b.module}, moving...))
+	fmt.Printf("bus upgrade %d: %s %s → %s on %s; streams snapshotted at %s; %s\n", step.ID, b.module, step.From,
+		short(b.to), strings.Join(moving, ", "), where, map[bool]string{true: "reversible: putting the old build back undoes it",
+			false: "NOT reversible: the snapshot is the only way back"}[*reversible])
+	sent, err := sendRollout(withBusStep(withScope(ctx, sendScope{person: true})), open, moving)
+	if err != nil {
+		_ = inv.EndBusStep(ctx, step.ID, "failed", "the send was refused: "+err.Error())
+		return fmt.Errorf("the bus's machine could not be sent its new build: %w — nothing was replaced", err)
+	}
+	fmt.Printf("sent %s; `bus-maintenance` is open until the bus answers healthy again — every stream, every durable "+
+		"consumer, a round trip to the machines (H-bus) — within %s, or the step is said failed with its snapshot "+
+		"as the way back. `bus` says how it went\n", strings.Join(sent, ", "), busStepBound)
+	return nil
+}
+
+// busStatus is `bus`: what an upgrade would do, and the last step.
+func busStatus(ctx context.Context) error {
+	open, err := openStores(ctx)
+	if err != nil {
+		return err
+	}
+	defer open.Close()
+	b, err := pendingBus(ctx, open.inventory)
+	if err != nil {
+		return err
+	}
+	if b.module == "" {
+		fmt.Println("the mesh holds no module that provides its bus")
+	} else {
+		fmt.Printf("the bus is %s, built %s, on %s; never rolled out — a planned step (`bus upgrade`)\n", b.module,
+			short(b.to), orNone(strings.Join(b.machines, ", ")))
+		for _, n := range b.machines {
+			state := "runs it"
+			if b.moves(n) {
+				state = "runs " + short(orNotKnown(b.from[n])) + ": `bus upgrade` replaces it"
+			}
+			fmt.Printf("  %-10s %s\n", n, state)
+		}
+	}
+	fmt.Println("  `bus upgrade` has the bus machine's backup holder snapshot the streams first (ADR 0235)")
+	s, found, err := open.inventory.LatestBusStep(ctx)
+	if err != nil || !found {
+		return err
+	}
+	state := "running since " + s.Started.Local().Format("2006-01-02 15:04")
+	if s.Ended != nil {
+		state = s.Outcome + " at " + s.Ended.Local().Format("2006-01-02 15:04")
+	}
+	fmt.Printf("last step %d: %s → %s on %s by %s (%s): %s; snapshot %s\n", s.ID, s.From, short(s.To),
+		strings.Join(s.Machines, ", "), orNone(s.By), s.Why, state, s.Snapshot)
+	if s.Found != "" {
+		fmt.Printf("  %s\n", s.Found)
+	}
+	return nil
+}
+
+// probeBusStep is DB: a bus upgrade running is said as `bus-maintenance`; the bus healthy again after
+// the machines reported the new build ends it done; past its bound, unhealthy, it ends failed and is
+// said — urgent, with its snapshot — while the bus is still not healthy.
+func probeBusStep(ctx context.Context, d *doctor) ([]conditions.Observation, error) {
+	inv := d.open.inventory
+	s, found, err := inv.LatestBusStep(ctx)
+	if err != nil || !found {
+		return nil, err
+	}
+	if s.Ended != nil && s.Outcome != "failed" {
+		return nil, nil
+	}
+	problems, err := busHealth(ctx, d)
+	if err != nil {
+		return nil, err
+	}
+	reports, err := inv.LastReports(ctx)
+	if err != nil {
+		return nil, err
+	}
+	applied := true
+	for _, r := range reports {
+		for _, n := range s.Machines {
+			if r.Node == n && (!r.Current || r.Outcome != inventory.OutcomeApplied || r.At == nil || r.At.Before(s.Started)) {
+				applied = false
+				problems = append(problems, n+" has not reported the new bus applied")
+			}
+		}
+	}
+	id := s.Module
+	if s.Ended == nil {
+		switch {
+		case applied && len(problems) == 0:
+			return nil, inv.EndBusStep(ctx, s.ID, "done", "the bus answered healthy after the upgrade")
+		case time.Since(s.Started) > busStepBound:
+			found := strings.Join(problems, "; ")
+			if err := inv.EndBusStep(ctx, s.ID, "failed", found); err != nil {
+				return nil, err
+			}
+			s.Found = found
+		default:
+			return []conditions.Observation{{Scope: conditions.ScopeBus, ID: id, Token: "maintenance",
+				Kind: kindBusMaintenance, Severity: conditions.Warning,
+				Summary: fmt.Sprintf("the bus is being upgraded (step %d, %s → %s on %s, by %s: %s); its snapshot is %s",
+					s.ID, s.From, short(s.To), strings.Join(s.Machines, ", "), orNone(s.By), s.Why, s.Snapshot),
+				Said: orNone(strings.Join(problems, "; "))}}, nil
+		}
+	}
+	if len(problems) == 0 {
+		return nil, nil // failed, and healthy since: nothing wrong now
+	}
+	way := "put the old build back"
+	if !s.Reversible {
+		way = "restore the snapshot"
+	}
+	return []conditions.Observation{{Scope: conditions.ScopeBus, ID: id, Token: "upgrade-failed",
+		Kind: kindBusUpgradeFailed, Severity: conditions.Urgent, Resolver: conditions.ResolverOperator,
+		Summary: fmt.Sprintf("the bus upgrade (step %d, %s → %s) did not end healthy within %s: %s — the way back is to %s (%s)",
+			s.ID, s.From, short(s.To), busStepBound, strings.Join(problems, "; "), way, s.Snapshot)}}, nil
+}
+
+func sortedKeys(set map[string]bool) []string {
+	out := make([]string, 0, len(set))
+	for k := range set {
+		out = append(out, k)
+	}
+	sort.Strings(out)
+	return out
+}
+
+// busSnapshotWithin is how long the bus machine's backup holder is given to take the bus's snapshot.
+var busSnapshotWithin = 15 * time.Minute
+
+// snapshotTheBusNow asks the bus machine's backup holder to back the bus module up now — its dump is
+// the streams' snapshot (novox/hq ADR 0235) — and waits until it says a backup newer than the ask:
+// where the snapshot is, as a person reads it. The serving controller's connection, or one of its own.
+func snapshotTheBusNow(ctx context.Context, module, node string) (string, error) {
+	var where string
+	err := onTheBus(func(conn *nats.Conn) error {
+		asked := time.Now()
+		answer, err := link.AskSeatTool(ctx, conn, catalogue.BackupSeat, "now", node,
+			map[string]any{"module": module}, 30*time.Second)
+		if err != nil {
+			return fmt.Errorf("%s's backup holder was not asked to take the bus's snapshot: %w", node, err)
+		}
+		if answer.Error != "" {
+			return fmt.Errorf("%s's backup holder would not take the bus's snapshot: %s", node, answer.Error)
+		}
+		deadline := time.Now().Add(busSnapshotWithin)
+		for {
+			answer, err := link.AskSeatTool(ctx, conn, catalogue.BackupSeat, "backed-up", node, map[string]any{}, 10*time.Second)
+			if err == nil && answer.Error == "" {
+				if measured, err := readHolder(answer.Result); err == nil {
+					for item, m := range measured[module] {
+						if m.LastBackup != nil && m.LastBackup.After(asked) && m.Error == "" {
+							where = fmt.Sprintf("%s's restore point of %s (%s) taken %s", node, module, item,
+								m.LastBackup.UTC().Format(time.RFC3339))
+							return nil
+						}
+					}
+				}
+			}
+			if time.Now().After(deadline) {
+				return fmt.Errorf("%s's backup holder did not say the bus's snapshot was taken within %s; the bus is "+
+					"not replaced", node, busSnapshotWithin)
+			}
+			select {
+			case <-ctx.Done():
+				return ctx.Err()
+			case <-time.After(10 * time.Second):
+			}
+		}
+	})
+	return where, err
+}
+
+// errBusWaits is a send refused because it would replace the bus outside its planned step.
+var errBusWaits = errors.New("a new bus build waits for its planned step")
+
+type busStepKey struct{}
+
+// withBusStep marks a send as the bus's planned step: the one send that may replace the bus.
+func withBusStep(ctx context.Context) context.Context {
+	return context.WithValue(ctx, busStepKey{}, true)
+}
+
+func busStepSending(ctx context.Context) bool { on, _ := ctx.Value(busStepKey{}).(bool); return on }

cmd/mesh-controller/bus_users_closed_test.go

@@ -0,0 +1,92 @@
+package main
+
+import (
+	"errors"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// **Every user's slow consumer is S9's, not the controller's alone** (novox/hq ADR 0357, issue 270). On
+// 2026-10-07 the bus closed two clients on the laptop as slow consumers and nothing raised a condition:
+// the controller heard only its own connection. Said by the bus module and read back, a user the bus
+// closes is one condition naming the module and its machine, raised at the first look and cleared an hour
+// after the last closure.
+func TestAUserTheBusClosedAsASlowConsumerIsOneConditionNamingItsModuleAndMachine(t *testing.T) {
+	closed := time.Date(2026, 10, 14, 12, 0, 0, 0, time.UTC)
+	now := closed.Add(20 * time.Second)
+	store := conditions.NewInMemory()
+	k := conditions.NewKeeper(t.Context(), conditions.Options{Store: store, History: store,
+		Teller: &conditions.Told{}, Now: func() time.Time { return now }})
+	t.Cleanup(func() { k.Close(t.Context()) })
+
+	advisories := link.BusClosures([]link.BusClosure{
+		{User: "laptop.claude-code", CID: 10, Reason: "Slow Consumer (Write Deadline)", Opened: closed.Add(-time.Hour),
+			Closed: closed.Add(-10 * time.Minute)},
+		{User: "laptop.claude-code", CID: 44, Reason: "Slow Consumer (Write Deadline)", Opened: closed.Add(-time.Minute),
+			Closed: closed},
+		{User: "anchor.desk", CID: 7, Reason: "Maximum Message Payload Exceeded", Opened: closed.Add(-time.Hour),
+			Closed: closed},
+	}, []string{link.AdvisorySlowConsumer, link.AdvisorySlowConsumer, link.AdvisoryConnectionClosed}, closed.Add(-time.Hour))
+	look := func() {
+		t.Helper()
+		f := &signalFacts{now: now, host: "anchor", advisories: advisories}
+		if err := k.Reconcile(t.Context(), "S9", watchAdvisories(f)); err != nil {
+			t.Fatal(err)
+		}
+	}
+	look()
+
+	slow, found, err := conditions.ReadOne(t.Context(), store, "bus.laptop.claude-code.slow-consumer")
+	if err != nil || !found {
+		t.Fatalf("no slow-consumer condition for the user: %v %v", found, err)
+	}
+	if slow.Subject.Machine != "laptop" || slow.Observations != 2 || !slow.LastObserved.Equal(closed) {
+		t.Fatalf("the slow consumer is said on %q, %d closure(s), last %s: %+v", slow.Subject.Machine, slow.Observations,
+			slow.LastObserved, slow)
+	}
+	if !strings.Contains(slow.Summary, "claude-code on laptop") || strings.Contains(slow.Summary, "laptop.claude-code") {
+		t.Fatalf("the summary does not name the module in words, or carries the dotted user: %q", slow.Summary)
+	}
+	if !strings.Contains(slow.Headline, "Claude-code on laptop") {
+		t.Fatalf("the headline is %q", slow.Headline)
+	}
+	cut, found, err := conditions.ReadOne(t.Context(), store, "bus.anchor.desk.connection-closed")
+	if err != nil || !found || cut.Subject.Machine != "anchor" || !strings.Contains(cut.Summary, "maximum message payload exceeded") {
+		t.Fatalf("the user cut off for breaking the bus's rules: %v %v %+v", found, err, cut)
+	}
+
+	// An hour after the newest closure without another, both clear.
+	now = closed.Add(time.Hour + time.Minute)
+	look()
+	for _, key := range []string{"bus.laptop.claude-code.slow-consumer", "bus.anchor.desk.connection-closed"} {
+		if _, found, _ := k.Get(t.Context(), key); found {
+			t.Fatalf("%s is still open an hour after the last closure", key)
+		}
+	}
+}
+
+// **A read of the bus module's events that fails does not blind S9** (review of #326): the controller's own
+// signals are still said, and the failed read is a condition of its own.
+func TestABusModuleReadThatFailsKeepsTheControllersOwnSignals(t *testing.T) {
+	at := time.Date(2026, 10, 14, 12, 0, 0, 0, time.UTC)
+	f := &signalFacts{now: at.Add(time.Minute), host: "anchor",
+		advisories: []link.Advisory{{Kind: link.AdvisorySlowConsumer, ID: "controller", Said: "the controller fell behind",
+			First: at, Last: at, Count: 1}},
+		busFaultsErr: errors.New("nats: timeout")}
+	keys := map[string]bool{}
+	for _, o := range watchAdvisories(f) {
+		keys[o.Key()] = true
+	}
+	if !keys["bus.controller.slow-consumer"] || !keys["bus.bus-module.bus-faults-unread"] {
+		t.Fatalf("observed %v: the controller's own slow consumer and the unread events, both", keys)
+	}
+	for _, row := range signalsTable {
+		if row.Row == "S9" && row.needs(f) != nil {
+			t.Fatal("the S9 row went blind for a read of the bus module's events")
+		}
+	}
+}

cmd/mesh-controller/bus_waits.go

@@ -0,0 +1,195 @@
+package main
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// A send held for the bus's planned step (novox/hq issue 336).
+//
+// **A wait only a person can end is said to that person at once.** No send replaces the bus but its planned
+// step (sendToEach, ADR 0236), and the step is a person's `bus upgrade`. So while a new bus build waits, every
+// walk whose tier sends to the bus's machine is refused, and tries again each tick. The refusal was kept only
+// as the walk's note; nothing was raised, and the operator found the hold by asking why a walk did not move.
+// Row S17 raises it on the first tick after the first refusal, in the bus's scope, for the operator: what
+// waits, behind which bus build, since when, and the verb. A walk held only by it is not late, so S3 leaves it
+// out, as it leaves out a walk under a paused build seat. It clears once the bus's machine has been sent the
+// build the mesh holds — the step was taken, and no send is refused for the bus any more — whatever the walks'
+// notes still say. Whether the new bus came up healthy is the step's own condition (probe DB).
+
+// kindBusStepWaiting is S17's kind: bus.<module>.step-waiting.
+const kindBusStepWaiting = "bus-step-waiting"
+
+// busFacts is a new bus build waiting for its planned step, and the sends held for it.
+type busFacts struct {
+	module, to string
+	// from is the build each machine of the bus runs; machines those whose bus the step would replace.
+	from     map[string]string
+	machines []string
+	waits    []busWaitFacts
+}
+
+// busWaitFacts is one walk whose send was refused because it would replace the bus.
+type busWaitFacts struct {
+	plan, repository, commit string
+	// modules are what its tier sends: what waits.
+	modules []string
+	// since is the first refusal: as this controller saw it, or, read back, the save that kept the refusal.
+	since time.Time
+}
+
+// busRefusedFirst is when this controller first saw each walk refused for the bus's step. The walk's note
+// keeps the refusal across a restart; this keeps its moment more exactly than the walk's last save.
+var busRefusedFirst = &firstSeen{at: map[string]time.Time{}}
+
+type firstSeen struct {
+	mu sync.Mutex
+	at map[string]time.Time
+}
+
+// mark keeps the first moment an id was seen.
+func (s *firstSeen) mark(id string, at time.Time) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if _, seen := s.at[id]; !seen {
+		s.at[id] = at
+	}
+}
+
+// of is when an id was first seen; zero when it was not.
+func (s *firstSeen) of(id string) time.Time {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.at[id]
+}
+
+// keepOnly forgets every id not given: a walk no longer held is not held since then.
+func (s *firstSeen) keepOnly(ids map[string]bool) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	for id := range s.at {
+		if !ids[id] {
+			delete(s.at, id)
+		}
+	}
+}
+
+// refusedForTheBus is whether an error is the refusal of a send for the bus's planned step.
+func refusedForTheBus(err error) bool {
+	return err != nil && strings.Contains(err.Error(), errBusWaits.Error())
+}
+
+// busWaitsOf is the sends held for the bus's step, from the open walks: each walk not waiting for its
+// delivery's word whose note keeps a refusal for this very bus build, while the build would still replace
+// the bus on a machine. first is when this controller first saw a walk refused, zero when it did not.
+func busWaitsOf(plans []inventory.Plan, b busPending, first func(string) time.Time) busFacts {
+	f := busFacts{module: b.module, to: b.to, from: b.from}
+	for _, n := range b.machines {
+		if b.moves(n) {
+			f.machines = append(f.machines, n)
+		}
+	}
+	if len(f.machines) == 0 {
+		return f
+	}
+	for _, p := range plans {
+		if !p.Open() || p.Waiting() || !strings.Contains(p.Note, errBusWaits.Error()) || !strings.Contains(p.Note, short(b.to)) {
+			continue
+		}
+		since := p.Updated
+		if seen := first(p.ID); !seen.IsZero() && (since.IsZero() || seen.Before(since)) {
+			since = seen
+		}
+		var modules []string
+		if p.Tier >= 0 && p.Tier < len(p.Tiers) {
+			modules = append(modules, p.Tiers[p.Tier]...)
+		} else {
+			modules = planModules(p)
+		}
+		sort.Strings(modules)
+		f.waits = append(f.waits, busWaitFacts{plan: p.ID, repository: p.Repository, commit: p.Commit, modules: modules,
+			since: since})
+	}
+	sort.Slice(f.waits, func(i, j int) bool { return f.waits[i].since.Before(f.waits[j].since) })
+	return f
+}
+
+// heldByTheBus is the walks of a bus's facts, by id: what S3 leaves out.
+func (b busFacts) heldByTheBus() map[string]bool {
+	out := map[string]bool{}
+	for _, w := range b.waits {
+		out[w.plan] = true
+	}
+	return out
+}
+
+// busUpgradeVerb is the call that ends the wait, as the summary names it: through the mesh MCP server, with
+// why, saying whether the new version can be undone ("reversible": "true") or not ("irreversible": "true").
+const busUpgradeVerb = "`mesh_call mesh-controller.bus {\"upgrade\": \"true\", \"why\": \"…\", \"reversible\" or \"irreversible\": \"true\"}`"
+
+// watchBusWaits is S17: a send held for the bus's planned step, said at once to the operator.
+func watchBusWaits(f *signalFacts) []conditions.Observation {
+	b := f.bus
+	if len(b.waits) == 0 || len(b.machines) == 0 {
+		return nil
+	}
+	since := b.waits[0].since
+	var walks, what []string
+	for _, w := range b.waits {
+		walks = append(walks, fmt.Sprintf("%s (%s %s, tier: %s)", w.plan, w.repository, short(w.commit),
+			strings.Join(w.modules, ", ")))
+		what = append(what, deliveryWhat(w.modules, w.repository))
+	}
+	var from []string
+	for _, n := range b.machines {
+		from = append(from, short(orNotKnown(b.from[n])))
+	}
+	machines := namesWords(b.machines, 3)
+	in := f.now.Sub(since)
+	return []conditions.Observation{{Scope: conditions.ScopeBus, ID: b.module, Token: "step-waiting",
+		Kind: kindBusStepWaiting, Severity: conditions.Warning, Resolver: conditions.ResolverOperator,
+		Machine: b.machines[0], Also: b.machines[1:],
+		Summary: fmt.Sprintf("sends to %s wait for the bus's planned step: a new bus build (%s %s → %s) would replace "+
+			"the bus there, which only a person's %s does; waiting since %s: %s", strings.Join(b.machines, ", "),
+			b.module, strings.Join(sortedUnique(from), ", "), short(b.to), busUpgradeVerb,
+			since.UTC().Format(time.RFC3339), strings.Join(walks, "; ")),
+		Said:     fmt.Sprintf("%d walk(s) refused since %s", len(b.waits), since.UTC().Format(time.RFC3339)),
+		Headline: clipWords("Sends to "+machines+" wait for a bus upgrade", conditions.HeadlineMax),
+		Explanation: clipWords(fmt.Sprintf("A new version of the mesh's message system is built, and only a person "+
+			"installs it. Until then nothing else is sent to %s: %s waits, for %s so far.", machines,
+			namesWords(sortedUnique(what), 3), humanDuration(in)), conditions.ExplanationMax),
+		Needs:    "start the bus upgrade " + FromMeshMCPServer,
+		Resolved: "Resolved: the bus upgrade started, and sends go on"}}
+}
+
+// sortedUnique is a list sorted, each once.
+func sortedUnique(xs []string) []string {
+	seen := map[string]bool{}
+	var out []string
+	for _, x := range xs {
+		if !seen[x] {
+			seen[x] = true
+			out = append(out, x)
+		}
+	}
+	sort.Strings(out)
+	return out
+}
+
+// clipWords keeps a plain sentence within a bound, at a word.
+func clipWords(s string, n int) string {
+	if len(s) <= n {
+		return s
+	}
+	cut := strings.LastIndex(s[:n-1], " ")
+	if cut <= 0 {
+		cut = n - 1
+	}
+	return s[:cut] + "…"
+}

cmd/mesh-controller/bus_waits_integration_test.go

@@ -0,0 +1,70 @@
+//go:build integration
+
+package main
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+func TestASendHeldForTheBusStepIsFoundFromTheWalksItHolds(t *testing.T) {
+	now := time.Date(2026, 10, 8, 18, 30, 0, 0, time.UTC)
+	b := aBusOnAnchor()
+	walk := func(id, repo, note string, updated time.Time) inventory.Plan {
+		return inventory.Plan{ID: id, Repository: repo, Commit: "c0ffee001122", State: inventory.PlanRolling, Tier: 0,
+			Tiers: [][]string{{"mesh-host"}}, Modules: map[string]*inventory.PlanModule{"mesh-host": {}}, Note: note,
+			Updated: updated}
+	}
+	for _, c := range []struct {
+		name  string
+		bus   busPending
+		plans []inventory.Plan
+		first map[string]time.Time
+		want  []string
+		since time.Time
+	}{
+		{"a walk refused for the bus", b,
+			[]inventory.Plan{walk("plan-1", "novox/mesh-host", refusedNote(b, 0), now.Add(-27*time.Minute))}, nil,
+			[]string{"plan-1"}, now.Add(-27 * time.Minute)},
+		{"refused earlier than its last save, as this controller saw it", b,
+			[]inventory.Plan{walk("plan-1", "novox/mesh-host", refusedNote(b, 0), now.Add(-5*time.Minute))},
+			map[string]time.Time{"plan-1": now.Add(-28 * time.Minute)}, []string{"plan-1"}, now.Add(-28 * time.Minute)},
+		{"a walk refused for another reason", b,
+			[]inventory.Plan{walk("plan-1", "novox/mesh-host", "tier 0: the build seat is paused — tried again", now)}, nil,
+			nil, time.Time{}},
+		{"refused for an older bus build than the one held now", func() busPending { o := b; o.to = "99999999cccc"; return o }(),
+			[]inventory.Plan{walk("plan-1", "novox/mesh-host", refusedNote(b, 0), now)}, nil, nil, time.Time{}},
+		{"the bus already runs the build held: its step started", func() busPending {
+			o := aBusOnAnchor()
+			o.from = map[string]string{"anchor": o.to}
+			return o
+		}(), []inventory.Plan{walk("plan-1", "novox/mesh-host", refusedNote(b, 0), now)}, nil, nil, time.Time{}},
+		{"a walk waiting for its delivery's word asks no send", b, func() []inventory.Plan {
+			p := walk("plan-1", "novox/mesh-host", refusedNote(b, 0), now)
+			p.Delivery = &inventory.PlanDelivery{Awaits: "mesh-delivery"}
+			return []inventory.Plan{p}
+		}(), nil, nil, time.Time{}},
+	} {
+		t.Run(c.name, func(t *testing.T) {
+			got := busWaitsOf(c.plans, c.bus, func(id string) time.Time { return c.first[id] })
+			var ids []string
+			for _, w := range got.waits {
+				ids = append(ids, w.plan)
+			}
+			if strings.Join(ids, ",") != strings.Join(c.want, ",") {
+				t.Fatalf("held for the bus: %v, want %v", ids, c.want)
+			}
+			if len(c.want) > 0 {
+				if !got.waits[0].since.Equal(c.since) {
+					t.Errorf("waiting since %s, want %s", got.waits[0].since, c.since)
+				}
+				if strings.Join(got.machines, ",") != "anchor" || got.to != b.to || got.module != "nats" {
+					t.Errorf("behind %+v", got)
+				}
+			}
+		})
+	}
+}

cmd/mesh-controller/bus_waits_test.go

@@ -0,0 +1,99 @@
+package main
+
+import (
+	"context"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+)
+
+// novox/hq issue 336: a send held because it would replace the bus outside its planned step waits for a
+// person, so a person is told at once — what waits, behind which bus build, since when, and the verb that
+// ends it — and the wait is not read as a walk running late.
+
+// aBusOnAnchor is a new bus build waiting for its step on anchor: nats 88135ad0 there, 32307bd1 held.
+func aBusOnAnchor() busPending {
+	return busPending{module: "nats", machines: []string{"anchor"}, from: map[string]string{"anchor": "88135ad0aaaa"},
+		to: "32307bd1bbbb", same: map[string]bool{}}
+}
+
+// refusedNote is the note a walk keeps when its send was refused for the bus, as advanceHeld writes it.
+func refusedNote(b busPending, tier int) string {
+	held := "sending anchor would replace the bus (nats " + short(b.from["anchor"]) + " → " + short(b.to) +
+		"), which is a planned step: `bus upgrade --why …` snapshots its streams first and checks them after (novox/hq ADR 0236)"
+	return "tier " + string(rune('0'+tier)) + ": " + errBusWaits.Error() + ": " + held + " — tried again"
+}
+
+// **Said at once, not as lateness, and cleared when the step starts**: the walk held only for the bus raises
+// the bus's condition on the first tick, before any tier bound, naming what waits, the bus build from and to,
+// since when and `bus upgrade`, for the operator; S3 says nothing of it even past its bound; and the
+// condition clears once the bus's machine runs the new build.
+func TestASendHeldForTheBusStepIsSaidAtOnceAndNotAsLateness(t *testing.T) {
+	now := time.Date(2026, 10, 8, 18, 30, 0, 0, time.UTC)
+	b := aBusOnAnchor()
+	held := func(entered time.Duration) *signalFacts {
+		f := calm(now)
+		f.plans = []planFacts{{id: "plan-1", repository: "novox/mesh-host", commit: "c0ffee00", tier: 0, tiers: 1,
+			entered: now.Add(-entered), bound: 30 * time.Minute, waiting: refusedNote(b, 0), bus: true}}
+		f.bus = busFacts{module: "nats", to: b.to, from: b.from, machines: []string{"anchor"},
+			waits: []busWaitFacts{{plan: "plan-1", repository: "novox/mesh-host", commit: "c0ffee001122",
+				modules: []string{"mesh-host"}, since: now.Add(-time.Minute)}}}
+		return f
+	}
+
+	f := held(time.Minute)
+	got := watchBusWaits(f)
+	if len(got) != 1 {
+		t.Fatalf("a send held for the bus a minute ago raised %+v", got)
+	}
+	o := got[0]
+	if o.Key() != "bus.nats.step-waiting" || o.Kind != kindBusStepWaiting || o.Resolver != conditions.ResolverOperator {
+		t.Fatalf("raised %s (%s), resolver %q", o.Key(), o.Kind, o.Resolver)
+	}
+	for _, want := range []string{"anchor", "mesh-host", "88135ad0", "32307bd1", "mesh_call mesh-controller.bus",
+		`"upgrade": "true"`, `"reversible"`, `"irreversible"`, "2026-10-08T18:29:00Z", "plan-1"} {
+		if !strings.Contains(o.Summary, want) {
+			t.Errorf("its summary does not say %q: %s", want, o.Summary)
+		}
+	}
+	if !strings.Contains(o.Explanation, "mesh-host") || !strings.Contains(o.Headline, "bus upgrade") || o.Needs == "" {
+		t.Errorf("its words do not say what waits and what the operator does: %+v", o)
+	}
+	if why, ok := conditions.PlainWords(conditions.Words{Headline: o.Headline, Explanation: o.Explanation,
+		Resolved: o.Resolved, Needs: o.Needs}, "anchor"); !ok {
+		t.Errorf("its words are not plain: %s", why)
+	}
+
+	// Past S3's bound: still the bus's wait, never a stalled walk.
+	late := held(45 * time.Minute)
+	if s3 := watchPlans(late); len(s3) != 0 {
+		t.Fatalf("a walk held only by the bus step was said stalled: %+v", s3)
+	}
+	// A walk held for something else past its bound is still stalled.
+	other := held(45 * time.Minute)
+	other.plans[0].bus = false
+	if s3 := watchPlans(other); len(s3) != 1 {
+		t.Fatalf("a walk held for something else past its bound raised %+v", s3)
+	}
+
+	// Through the keeper: open at the first tick, cleared when the step started.
+	store := conditions.NewInMemory()
+	k := conditions.NewKeeper(t.Context(), conditions.Options{Store: store, History: store, Teller: &conditions.Told{},
+		Now: func() time.Time { return now }})
+	defer k.Close(context.Background())
+	w := &watchdogs{keeper: k, started: now.Add(-time.Hour)}
+	w.see(t.Context(), held(time.Minute))
+	open, err := k.Open(t.Context())
+	if err != nil || len(open) != 1 || open[0].Key != "bus.nats.step-waiting" {
+		t.Fatalf("after the first tick, open: %+v (%v)", open, err)
+	}
+	started := held(time.Minute)
+	started.bus = busFacts{module: "nats", to: b.to}
+	started.plans[0].bus = false
+	w.see(t.Context(), started)
+	if open, _ := k.Open(t.Context()); len(open) != 0 {
+		t.Fatalf("the step started, and open: %+v", open)
+	}
+}

cmd/mesh-controller/buscertificate.go

@@ -0,0 +1,258 @@
+package main
+
+import (
+	"context"
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
+	"errors"
+	"fmt"
+	"math/big"
+	"net"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/broker"
+)
+
+// The bus's own certificate, made by the mesh rather than borrowed from an image.
+//
+// **The foundation asked a third-party image for a tool it never said must be there** (novox/hq
+// 04-ISSUES/146). The bootstrap made this certificate by running `openssl` inside the broker's
+// image, which worked while the broker was one that happened to carry it and stopped the day the
+// bus changed: the new one has a shell and no openssl, so the step exited 127 and no mesh could be
+// raised. Substituting another image the bundle names does not help — none of them carry it
+// either.
+//
+// So the program that needs a certificate makes one. It is the mesh's own binary, already on the
+// machine at this point in the bootstrap (the schema step ran it), and it needs nothing from the
+// image it writes into but a mounted directory.
+//
+// **Self-signed, and that is the design** — a host pins this server's exact certificate and
+// authenticates with a password (novox/hq ADR 0004). There is no authority above it to ask, and at
+// this moment in a bootstrap there is no mesh to ask one of.
+//
+// Idempotent, because the step is applied again on every reconcile and a second certificate would
+// be one the hosts that pinned the first no longer believe.
+
+// busCertificateNames is what the bus is reached by: the container name on a mesh network, and the
+// loopback address the machine's own foundation dials.
+var busCertificateNames = []string{"mesh-broker"}
+
+const busCertificateLife = 10 * 365 * 24 * time.Hour
+
+// busCertificate makes the bus's certificate in a directory, or says whether one is there.
+//
+//	broker certificate --into /tls           make it if it is not there
+//	broker certificate --check --into /tls   exit non-zero unless a usable pair is
+func busCertificate(args []string) error {
+	into, check := "", false
+	for i := 0; i < len(args); i++ {
+		switch args[i] {
+		case "--check":
+			check = true
+		case "--into":
+			if i+1 >= len(args) {
+				return errors.New("--into needs a directory")
+			}
+			into = args[i+1]
+			i++
+		default:
+			return fmt.Errorf("broker certificate [--check] --into <directory>: %q", args[i])
+		}
+	}
+	if into == "" {
+		return errors.New("broker certificate [--check] --into <directory>")
+	}
+	crt, key := filepath.Join(into, "tls.crt"), filepath.Join(into, "tls.key")
+
+	if usable, err := busCertificateUsable(crt, key); err != nil {
+		return err
+	} else if usable {
+		fmt.Printf("the bus already has a certificate at %s, and it was left alone\n", crt)
+		return nil
+	}
+	if check {
+		// Said as a failure, because that is what the caller asked: a bootstrap's verify runs
+		// this and a false answer is what makes the step run.
+		return fmt.Errorf("no usable certificate and key at %s", into)
+	}
+	return writeBusCertificate(crt, key)
+}
+
+// busCertificateUsable says whether a certificate and its key are both there and parse.
+//
+// Both, and parsed rather than stat'ed: a half-written pair is the state a bootstrap interrupted
+// between the two files leaves behind, and a step that treated it as done would hand the server a
+// certificate with no key and report success.
+func busCertificateUsable(crt, key string) (bool, error) {
+	certPEM, err := os.ReadFile(crt)
+	if errors.Is(err, os.ErrNotExist) {
+		return false, nil
+	}
+	if err != nil {
+		return false, err
+	}
+	keyPEM, err := os.ReadFile(key)
+	if errors.Is(err, os.ErrNotExist) {
+		return false, nil
+	}
+	if err != nil {
+		return false, err
+	}
+	if _, err := tlsPairParses(certPEM, keyPEM); err != nil {
+		return false, nil
+	}
+	return true, nil
+}
+
+func tlsPairParses(certPEM, keyPEM []byte) (*x509.Certificate, error) {
+	block, _ := pem.Decode(certPEM)
+	if block == nil || block.Type != "CERTIFICATE" {
+		return nil, errors.New("not a certificate")
+	}
+	certificate, err := x509.ParseCertificate(block.Bytes)
+	if err != nil {
+		return nil, err
+	}
+	keyBlock, _ := pem.Decode(keyPEM)
+	if keyBlock == nil {
+		return nil, errors.New("not a key")
+	}
+	if _, err := x509.ParsePKCS8PrivateKey(keyBlock.Bytes); err != nil {
+		if _, err := x509.ParsePKCS1PrivateKey(keyBlock.Bytes); err != nil {
+			return nil, err
+		}
+	}
+	return certificate, nil
+}
+
+func writeBusCertificate(crt, key string) error {
+	private, err := rsa.GenerateKey(rand.Reader, 2048)
+	if err != nil {
+		return err
+	}
+	serial, err := rand.Int(rand.Reader, new(big.Int).Lsh(big.NewInt(1), 128))
+	if err != nil {
+		return err
+	}
+	template := &x509.Certificate{
+		SerialNumber:          serial,
+		Subject:               pkix.Name{CommonName: busCertificateNames[0]},
+		DNSNames:              busCertificateNames,
+		IPAddresses:           []net.IP{net.ParseIP("127.0.0.1")},
+		NotBefore:             time.Now().Add(-time.Hour),
+		NotAfter:              time.Now().Add(busCertificateLife),
+		KeyUsage:              x509.KeyUsageDigitalSignature | x509.KeyUsageKeyEncipherment,
+		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
+		BasicConstraintsValid: true,
+	}
+	der, err := x509.CreateCertificate(rand.Reader, template, template, &private.PublicKey, private)
+	if err != nil {
+		return err
+	}
+	pkcs8, err := x509.MarshalPKCS8PrivateKey(private)
+	if err != nil {
+		return err
+	}
+
+	// **The key first, and only then the certificate**, so the pair a reader finds is never a
+	// certificate whose key has not been written yet — the one order in which an interruption
+	// leaves something that looks finished (novox/hq 04-ISSUES/014, a key present and unusable).
+	if err := os.WriteFile(key, pem.EncodeToMemory(&pem.Block{Type: "PRIVATE KEY", Bytes: pkcs8}), 0o600); err != nil {
+		return err
+	}
+	if err := os.WriteFile(crt, pem.EncodeToMemory(&pem.Block{Type: "CERTIFICATE", Bytes: der}), 0o644); err != nil {
+		return err
+	}
+	fmt.Printf("made the bus a certificate for %v, valid until %s\n  %s\n  %s\n",
+		busCertificateNames, template.NotAfter.Format(time.RFC3339), crt, key)
+	return nil
+}
+
+// busAccounts writes the mesh's composed user list to a file.
+//
+// **For genesis, where no declaration can deliver it** (novox/hq 04-ISSUES/146). Everywhere else
+// the list reaches the machine running the bus as a resource of the module that holds it — which
+// requires that machine to be an enrolled node, and at genesis it is not: the first node cannot
+// enrol because the account it would enrol with cannot be composed onto a bus it has no declaration
+// for. The installer breaks that circle by placing the file itself, once, and the module takes the
+// file over from its first push.
+//
+// The same composition, not a second one: this asks the store for the same records and renders them
+// with the same composer the declaration uses. A genesis that hand-wrote an account would be a
+// second statement of who may say what, able to disagree with the first.
+//
+// **It writes to standard output unless told a file**, and that is the point: the control plane
+// composes and says what it composed, and whoever is raising the machine puts it where that
+// machine's bus reads it. A control plane that wrote into the bus's own directory would have to
+// know where that is and how to make the server re-read it — which is the module's knowledge, and
+// the module is what takes this over on the first push.
+//
+//	broker accounts > /var/lib/mesh-bus-conf/accounts.conf
+func busAccounts(ctx context.Context, args []string) error {
+	into := ""
+	for i := 0; i < len(args); i++ {
+		switch args[i] {
+		case "--into":
+			if i+1 >= len(args) {
+				return errors.New("--into needs a file")
+			}
+			into = args[i+1]
+			i++
+		default:
+			return fmt.Errorf("broker accounts --into <file>: %q", args[i])
+		}
+	}
+
+	open, err := openStores(ctx)
+	if err != nil {
+		return err
+	}
+	defer open.Close()
+
+	records, err := open.inventory.BusRecords(ctx)
+	if err != nil {
+		return err
+	}
+	users, err := broker.Users(records)
+	if err != nil {
+		return err
+	}
+	kept, err := open.inventory.BusUsers(ctx)
+	if err != nil {
+		return err
+	}
+	hashes := make(map[string]string, len(kept))
+	for name, u := range kept {
+		hashes[name] = u.PasswordHash
+	}
+	filled, missing := broker.WithPasswords(users, hashes)
+	if len(missing) > 0 {
+		// To standard error, always: the composed file may be going to standard output, and a
+		// remark in the middle of it is a configuration the server refuses to parse.
+		fmt.Fprintf(os.Stderr, "leaving out %d user(s) the mesh has minted no credential for: %s\n",
+			len(missing), strings.Join(missing, ", "))
+	}
+	if len(filled) == 0 {
+		return errors.New("not one user has a credential, so this list would refuse every " +
+			"connection in the mesh")
+	}
+	accounts, err := broker.ComposeAccounts(filled)
+	if err != nil {
+		return err
+	}
+	if into == "" {
+		fmt.Print(accounts)
+		return nil
+	}
+	if err := os.WriteFile(into, []byte(accounts), 0o600); err != nil {
+		return err
+	}
+	fmt.Printf("wrote %d user(s) to %s\n", len(filled), into)
+	return nil
+}

cmd/mesh-controller/buscertificate_test.go

@@ -0,0 +1,121 @@
+package main
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+// novox/hq 04-ISSUES/146. The bootstrap could not make the bus a certificate: it asked an image for
+// `openssl` and the image it asks has none. What replaces it is this command, so what is checked is
+// what the bootstrap needs from it — a pair a TLS server can actually load, made once and only once.
+
+func TestTheBusCertificateLoadsAsAServersWould(t *testing.T) {
+	into := t.TempDir()
+	if err := busCertificate([]string{"--into", into}); err != nil {
+		t.Fatalf("the bus could not be given a certificate: %v", err)
+	}
+
+	// The check a cheaper test would not make. The key was present and valid and the server could
+	// not start, once, because nothing loaded the pair the way a server loads it
+	// (novox/hq 04-ISSUES/014).
+	pair, err := tls.LoadX509KeyPair(filepath.Join(into, "tls.crt"), filepath.Join(into, "tls.key"))
+	if err != nil {
+		t.Fatalf("a TLS server cannot load what was written: %v", err)
+	}
+	leaf := pair.Leaf
+	if leaf == nil {
+		if leaf, err = x509.ParseCertificate(pair.Certificate[0]); err != nil {
+			t.Fatal(err)
+		}
+	}
+	if err := leaf.VerifyHostname("mesh-broker"); err != nil {
+		t.Errorf("the certificate is not for the name the bus is reached by: %v", err)
+	}
+	if len(leaf.IPAddresses) == 0 || leaf.IPAddresses[0].String() != "127.0.0.1" {
+		t.Errorf("the certificate does not cover the loopback address the foundation dials: %v", leaf.IPAddresses)
+	}
+
+	// The key is not readable by anything else on the machine; the certificate is public and is.
+	key, err := os.Stat(filepath.Join(into, "tls.key"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if key.Mode().Perm() != 0o600 {
+		t.Errorf("the key is %v", key.Mode().Perm())
+	}
+	crt, err := os.Stat(filepath.Join(into, "tls.crt"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if crt.Mode().Perm() != 0o644 {
+		t.Errorf("the certificate is %v, which the server runs as another user cannot read", crt.Mode().Perm())
+	}
+}
+
+// **Made once.** The step is applied again on every reconcile, and a second certificate is one the
+// hosts that pinned the first no longer believe (novox/hq ADR 0004).
+func TestTheBusCertificateIsMadeOnce(t *testing.T) {
+	into := t.TempDir()
+	if err := busCertificate([]string{"--into", into}); err != nil {
+		t.Fatal(err)
+	}
+	first, err := os.ReadFile(filepath.Join(into, "tls.crt"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := busCertificate([]string{"--into", into}); err != nil {
+		t.Fatal(err)
+	}
+	again, err := os.ReadFile(filepath.Join(into, "tls.crt"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if string(first) != string(again) {
+		t.Fatal("running it twice replaced the certificate every host had pinned")
+	}
+}
+
+// The verify half: false before, true after, which is what makes the bootstrap run the step at all.
+func TestTheCheckIsFalseUntilThereIsAPair(t *testing.T) {
+	into := t.TempDir()
+	if err := busCertificate([]string{"--check", "--into", into}); err == nil {
+		t.Fatal("an empty directory reported a usable certificate")
+	}
+	if err := busCertificate([]string{"--into", into}); err != nil {
+		t.Fatal(err)
+	}
+	if err := busCertificate([]string{"--check", "--into", into}); err != nil {
+		t.Fatalf("the certificate it just made does not satisfy its own check: %v", err)
+	}
+}
+
+// A half-written pair is not a pair. An interrupted bootstrap leaves exactly this, and a step that
+// called it done would hand the server a certificate with no key and report success.
+func TestACertificateWithoutItsKeyIsNotUsable(t *testing.T) {
+	into := t.TempDir()
+	if err := busCertificate([]string{"--into", into}); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.Remove(filepath.Join(into, "tls.key")); err != nil {
+		t.Fatal(err)
+	}
+	if err := busCertificate([]string{"--check", "--into", into}); err == nil {
+		t.Fatal("a certificate with no key passed the check")
+	}
+	if err := busCertificate([]string{"--into", into}); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := tls.LoadX509KeyPair(filepath.Join(into, "tls.crt"), filepath.Join(into, "tls.key")); err != nil {
+		t.Fatalf("it did not replace the unusable pair: %v", err)
+	}
+}
+
+func TestWhereToWriteIsRequired(t *testing.T) {
+	if err := busCertificate(nil); err == nil || !strings.Contains(err.Error(), "--into") {
+		t.Fatalf("it did not ask where to write: %v", err)
+	}
+}

cmd/mesh-controller/busobjects.go

@@ -0,0 +1,247 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+
+	"github.com/novox/mesh-controller/internal/broker"
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// The streams and durable consumers the mesh's own traffic needs, derived once (novox/hq to-be 45 §4,
+// D6 and D7).
+//
+// **What the controller asserts at its start and what the self-check expects to find are one
+// derivation**, run against the bus to make them and against a recorder to list them. Two lists would
+// drift, and a self-check comparing the bus with a second opinion of what should be there would find
+// the drift rather than the fault.
+
+// assertBusObjects brings every stream and consumer into being on r, and answers the machines that
+// can now hear a declaration.
+func assertBusObjects(ctx context.Context, inv *inventory.Inventory, r broker.Raiser) ([]string, error) {
+	nodes, err := inv.Nodes(ctx)
+	if err != nil {
+		return nil, err
+	}
+	names := make([]string, 0, len(nodes))
+	for _, n := range nodes {
+		names = append(names, n.Name)
+	}
+	if err := broker.Raise(r, names); err != nil {
+		return nil, err
+	}
+	// The work queues of the mesh's own roles (novox/hq ADR 0121). The queue before the holder,
+	// deliberately: work queues until somebody arrives to do it, so assigning a build machine a week
+	// after something started asking for builds flushes the backlog instead of having lost it.
+	// With the seats' holders, so each role's work queue gets the consumer its holder takes
+	// work from. Passed as nil until the first live raise, which left the build machine bound to a
+	// consumer nothing had created (2026-09-28).
+	holders, err := seatHolders(ctx, inv)
+	if err != nil {
+		return nil, err
+	}
+	if err := broker.RaiseSeats(r, inventory.MeshSeats(), holders); err != nil {
+		return nil, err
+	}
+	// And how every module hears what it consumes. Derived from the same records the user list is
+	// composed from, so a module the mesh grants a consumer's subjects has that consumer waiting.
+	// Done on every raise, not only when a credential is issued: every module moved onto this bus
+	// by the rollout was issued on the old one, and came up with nothing to bind to (2026-09-28).
+	consumers, records, err := moduleConsumersAndRecords(ctx, inv)
+	if err != nil {
+		return nil, err
+	}
+	// And a grant of a restricted stream that composes nothing, said on every raise and send (novox/hq ADR 0376 §2).
+	sayWithheld(records, "  ")
+	// And the work queues of seats that name their caller or their kind, with each holder's worker
+	// (novox/hq ADR 0259 §3): an ask queues until the router takes it, a channel's work until that kind
+	// takes it.
+	trafficStreams, trafficWorkers, err := seatTrafficObjects(ctx, inv)
+	if err != nil {
+		return nil, err
+	}
+	// And every module's own stream (novox/hq ADR 0363), from the catalogue, before the consumers on it.
+	modStreams, err := inv.DeclaredStreams(ctx)
+	if err != nil {
+		return nil, err
+	}
+	// Every one tried, and every failure named: one module's consumer the bus refuses is no reason
+	// the modules after it in the list hear nothing (novox/hq issue 208, where this runs on each send).
+	var failed []error
+	for _, s := range broker.ModuleStreams(modStreams) {
+		if err := r.EnsureStream(s); err != nil {
+			failed = append(failed, fmt.Errorf("the module stream %s: %w", s.Name, err))
+		}
+	}
+	for _, s := range trafficStreams {
+		if err := r.EnsureStream(s); err != nil {
+			failed = append(failed, fmt.Errorf("the work queue %s: %w", s.Name, err))
+		}
+	}
+	for _, c := range trafficWorkers {
+		if err := r.EnsureConsumer(c); err != nil {
+			failed = append(failed, fmt.Errorf("the worker %s on %s: %w", c.Name, c.Stream, err))
+		}
+	}
+	restricted := map[string]bool{}
+	for _, s := range modStreams {
+		restricted[s.Name] = s.Restricted
+	}
+	for _, c := range consumers {
+		if err := broker.EnsureHeard(r, c.Consumer, restricted[c.Consumer.Stream]); err != nil {
+			failed = append(failed, fmt.Errorf("how %s on %s hears what it consumes: %w", c.Module, c.Node, err))
+		}
+	}
+	// **And a consumer no longer granted loses what it reads through** (novox/hq ADR 0363 §6): every consumer
+	// on a module's stream the composition no longer asks for is removed, on this very send.
+	if p, prunes := r.(broker.Pruner); prunes && len(modStreams) > 0 {
+		var wanted []broker.Consumer
+		for _, c := range consumers {
+			wanted = append(wanted, c.Consumer)
+		}
+		removed, err := broker.PruneHeard(p, modStreams, wanted)
+		if err != nil {
+			failed = append(failed, err)
+		}
+		for _, gone := range removed {
+			fmt.Printf("  removed the consumer %s: its module is no longer granted that stream (novox/hq ADR 0363)\n", gone)
+		}
+	}
+	if len(failed) > 0 {
+		return nil, errors.Join(failed...)
+	}
+	return names, nil
+}
+
+// What raises the condition a send says when the objects it implies could not be asserted, and its kind.
+const (
+	sourceBusObjects         = "bus-objects"
+	kindBusObjectsUnasserted = "bus-objects-unasserted"
+)
+
+// assertOnSend asserts, on the bus a send is about to use, every object assertBusObjects derives —
+// **whenever a declaration is sent, not only when the controller starts** (novox/hq issue 208).
+//
+// A module assigned after the controller started was sent its declaration and found no consumer to
+// bind (`consumer not found`, messenger on 2026-10-06), and a seat holder assigned after it found no
+// worker: the objects a declaration implies were asserted at start and nowhere else, so they existed
+// only for what was assigned before the last restart. The same derivation, not a second list of what
+// a send needs: what start asserts, the self-check expects and a send asserts are one answer. Every
+// part is idempotent, so asserting the whole of it again is the no-op a restart already relies on.
+//
+// **A failure is said and raised, and the send goes on.** The objects are the mesh's, not the
+// machines' being sent: holding every machine back for one consumer that none of them may use would
+// turn one fault into all of them, and the declarations are not what is wrong. It is never silent —
+// said in the send's own output and raised as a condition, which the next send that asserts them
+// clears — and the start-time raise still refuses to serve without them.
+func assertOnSend(ctx context.Context, inv *inventory.Inventory, r broker.Raiser, indent string) error {
+	_, err := assertBusObjects(ctx, inv, r)
+	var observed []conditions.Observation
+	if err != nil {
+		fmt.Printf("%sTHE BUS DOES NOT HOLD WHAT THIS SEND IMPLIES: %v\n", indent, err)
+		fmt.Printf("%s  a module may find no consumer to bind, or a holder no worker; sent anyway, raised as "+
+			"condition %s, and asserted again by the next send\n", indent, unassertedObservation(err).Key())
+		observed = append(observed, unassertedObservation(err))
+	}
+	// Observed when it failed, cleared when it did not: a send that asserted everything is the
+	// observation that the bus holds what it should.
+	if kerr := withKeeper(ctx, func(k *conditions.Keeper) error {
+		return k.Reconcile(ctx, sourceBusObjects, observed)
+	}); kerr != nil {
+		fmt.Printf("%sand whether the bus holds what this send implies could not be kept as a condition: %v\n",
+			indent, kerr)
+	}
+	return err
+}
+
+// unassertedObservation is a send's failure to assert the bus's objects, as a condition.
+func unassertedObservation(err error) conditions.Observation {
+	return conditions.Observation{Scope: conditions.ScopeBus, ID: "objects", Token: "unasserted",
+		Kind: kindBusObjectsUnasserted, Severity: conditions.Warning, Source: sourceBusObjects,
+		Summary: "the bus's streams and consumers could not be asserted when a declaration was sent: " +
+			"a module may find no consumer to bind, or a seat's holder no worker",
+		Said: err.Error()}
+}
+
+// moduleConsumers is every module's durable consumer, from the records the user list is composed from.
+func moduleConsumers(ctx context.Context, inv *inventory.Inventory) ([]broker.ModuleConsumer, error) {
+	consumers, _, err := moduleConsumersAndRecords(ctx, inv)
+	return consumers, err
+}
+
+// moduleConsumersAndRecords is moduleConsumers with the records they were composed from.
+func moduleConsumersAndRecords(ctx context.Context, inv *inventory.Inventory) ([]broker.ModuleConsumer, broker.Records, error) {
+	records, err := inv.BusRecords(ctx)
+	if err != nil {
+		return nil, broker.Records{}, err
+	}
+	users, err := broker.Users(records)
+	if err != nil {
+		return nil, broker.Records{}, err
+	}
+	return broker.ConsumersOf(users), records, nil
+}
+
+// seatTrafficObjects is the work queues and workers of seats that name their caller or their kind, from
+// the records the user list is composed from.
+func seatTrafficObjects(ctx context.Context, inv *inventory.Inventory) ([]broker.Stream, []broker.Consumer, error) {
+	records, err := inv.BusRecords(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+	users, err := broker.Users(records)
+	if err != nil {
+		return nil, nil, err
+	}
+	streams, workers := broker.SeatTrafficObjects(users)
+	// And the queue of every such seat the catalogue declares, held or not: work queues from registration,
+	// so what is submitted before a holder is assigned waits for it (the correctness review of 2026-10-08).
+	declared, err := inv.DeclaredTrafficSeats(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+	have := map[string]bool{}
+	for _, s := range streams {
+		have[s.Name] = true
+	}
+	for _, s := range broker.TrafficQueues(declared) {
+		if !have[s.Name] {
+			streams = append(streams, s)
+			have[s.Name] = true
+		}
+	}
+	return streams, workers, nil
+}
+
+// moduleConsumerCount is how many modules hear what they consume, for the raise's one line.
+func moduleConsumerCount(ctx context.Context, inv *inventory.Inventory) (int, error) {
+	consumers, err := moduleConsumers(ctx, inv)
+	return len(consumers), err
+}
+
+// expectedBusObjects is every stream and consumer assertBusObjects would make, made nowhere.
+func expectedBusObjects(ctx context.Context, inv *inventory.Inventory) ([]broker.Stream, []broker.Consumer, error) {
+	var rec recordingRaiser
+	if _, err := assertBusObjects(ctx, inv, &rec); err != nil {
+		return nil, nil, fmt.Errorf("what the bus should hold cannot be worked out: %w", err)
+	}
+	return rec.streams, rec.consumers, nil
+}
+
+// recordingRaiser keeps what it was asked to assert and asserts nothing.
+type recordingRaiser struct {
+	streams   []broker.Stream
+	consumers []broker.Consumer
+}
+
+func (r *recordingRaiser) EnsureStream(s broker.Stream) error {
+	r.streams = append(r.streams, s)
+	return nil
+}
+
+func (r *recordingRaiser) EnsureConsumer(c broker.Consumer) error {
+	r.consumers = append(r.consumers, c)
+	return nil
+}

cmd/mesh-controller/busobjects_test.go

@@ -0,0 +1,199 @@
+//go:build integration
+
+package main
+
+import (
+	"errors"
+	"strings"
+	"testing"
+
+	"github.com/nats-io/nats.go"
+
+	"github.com/novox/mesh-controller/internal/broker"
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+
+	"github.com/novox/mesh-controller/internal/testbus"
+)
+
+// novox/hq issue 208: the bus's objects a declaration implies are asserted whenever one is sent, not
+// only when the controller starts.
+
+// aCarriedConsumer is the runtime on laptop and, carried by it, a module that consumes an event: the
+// shape of messenger on 2026-10-06, assigned after the controller started.
+func aCarriedConsumer(t *testing.T, open *stores) broker.Consumer {
+	t.Helper()
+	register(t, open, catalogue.Manifest{Module: catalogue.RuntimeModule, Version: "1",
+		OwnSecrets: catalogue.OwnSecrets{"broker": {Path: "/var/lib/mesh/node-tools/broker"}}})
+	register(t, open, catalogue.Manifest{Module: "messenger", Version: "1",
+		Consumes: []string{"billing.order.placed"}})
+	for _, m := range []string{catalogue.RuntimeModule, "messenger"} {
+		if _, err := open.inventory.Assign(t.Context(), "laptop", m); err != nil {
+			t.Fatal(err)
+		}
+	}
+	consumers, err := moduleConsumers(t.Context(), open.inventory)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, c := range consumers {
+		if c.Module == "messenger" && c.Node == "laptop" {
+			return c.Consumer
+		}
+	}
+	t.Fatalf("messenger on laptop is derived no consumer: %+v", consumers)
+	return broker.Consumer{}
+}
+
+// aLateHolder is a module holding the build agent's seat on anchor, assigned after the controller
+// started, and the worker its seat's queue should have for it.
+func aLateHolder(t *testing.T, open *stores) broker.Consumer {
+	t.Helper()
+	register(t, open, catalogue.Manifest{Module: "late-builder", Version: "1",
+		Claims: []catalogue.Claim{{Name: "node-build-agent", Scope: catalogue.ScopeNode}}})
+	if _, err := open.inventory.Assign(t.Context(), "anchor", "late-builder"); err != nil {
+		t.Fatal(err)
+	}
+	for _, s := range inventory.MeshSeats() {
+		if s.Name == "node-build-agent" {
+			c, needed := broker.HolderConsumerFor("anchor", "late-builder", s)
+			if !needed {
+				t.Fatal("the build agent's seat needs no worker")
+			}
+			return c
+		}
+	}
+	t.Fatal("the mesh declares no build agent's seat")
+	return broker.Consumer{}
+}
+
+// asserted says whether a recording holds a consumer by stream and name.
+func asserted(rec *recordingRaiser, want broker.Consumer) bool {
+	for _, c := range rec.consumers {
+		if c.Stream == want.Stream && c.Name == want.Name {
+			return true
+		}
+	}
+	return false
+}
+
+// What a send asserts includes what was assigned after the start's assertion: a carried module's
+// consumer and a late holder's worker. The derivation is the start's own, so this holds without a bus.
+func TestASendAssertsWhatWasAssignedAfterStart(t *testing.T) {
+	open := aMesh(t)
+	var atStart recordingRaiser
+	if _, err := assertBusObjects(t.Context(), open.inventory, &atStart); err != nil {
+		t.Fatal(err)
+	}
+	consumer := aCarriedConsumer(t, open)
+	worker := aLateHolder(t, open)
+	if asserted(&atStart, consumer) || asserted(&atStart, worker) {
+		t.Fatal("the start asserted what was not yet assigned; the test proves nothing")
+	}
+	var onSend recordingRaiser
+	if err := assertOnSend(t.Context(), open.inventory, &onSend, ""); err != nil {
+		t.Fatal(err)
+	}
+	if !asserted(&onSend, consumer) {
+		t.Fatalf("messenger's consumer %s on %s is not asserted by the send: %+v", consumer.Name, consumer.Stream, onSend.consumers)
+	}
+	if !asserted(&onSend, worker) {
+		t.Fatalf("the late holder's worker %s on %s is not asserted by the send: %+v", worker.Name, worker.Stream, onSend.consumers)
+	}
+}
+
+// failingRaiser refuses one consumer by name and records everything it was asked.
+type failingRaiser struct {
+	recordingRaiser
+	refuse string
+}
+
+func (f *failingRaiser) EnsureConsumer(c broker.Consumer) error {
+	f.consumers = append(f.consumers, c)
+	if c.Name == f.refuse {
+		return errors.New("nats: API error: code=503 description=insufficient resources")
+	}
+	return nil
+}
+
+// A send whose objects cannot be asserted says so in its output and raises a condition — and the next
+// send that asserts them clears it. The consumers after the refused one are still asked for.
+func TestASendThatCannotAssertTheBusSaysSoAndRaisesACondition(t *testing.T) {
+	open := aMesh(t)
+	consumer := aCarriedConsumer(t, open)
+	worker := aLateHolder(t, open)
+	failing := &failingRaiser{refuse: consumer.Name}
+
+	var sendErr error
+	out := stdoutOf(t, func() error {
+		sendErr = assertOnSend(t.Context(), open.inventory, failing, "  ")
+		return nil
+	})
+	if sendErr == nil || !strings.Contains(sendErr.Error(), "how messenger on laptop hears what it consumes") {
+		t.Fatalf("the failure is not answered: %v", sendErr)
+	}
+	if !strings.Contains(out, "THE BUS DOES NOT HOLD WHAT THIS SEND IMPLIES") ||
+		!strings.Contains(out, "insufficient resources") || !strings.Contains(out, "bus.objects.unasserted") {
+		t.Fatalf("the failure is not said in the send's output:\n%s", out)
+	}
+	if !asserted(&failing.recordingRaiser, worker) {
+		t.Fatal("the seat's worker was not asked for")
+	}
+	c, open1, err := conditionsFrom.Get(t.Context(), "bus.objects.unasserted")
+	if err != nil || !open1 {
+		t.Fatalf("no condition raised: %v", err)
+	}
+	if c.Kind != kindBusObjectsUnasserted || c.Source != sourceBusObjects ||
+		len(c.Evidence) == 0 || !strings.Contains(c.Evidence[0].Said, "insufficient resources") {
+		t.Fatalf("the condition does not say what failed: %+v", c)
+	}
+
+	// The next send asserts them, and that observation clears it.
+	if err := assertOnSend(t.Context(), open.inventory, &recordingRaiser{}, ""); err != nil {
+		t.Fatal(err)
+	}
+	if _, stillOpen, err := conditionsFrom.Get(t.Context(), "bus.objects.unasserted"); err != nil || stillOpen {
+		t.Fatalf("a send that asserted everything left the condition open: %v", err)
+	}
+}
+
+// Against a real bus, through the send's own grant: a module assigned after start has its consumer
+// once a declaration is sent, and a holder assigned after start its seat's worker.
+func TestNatsAModuleAssignedAfterStartGetsItsConsumerAtItsFirstSend(t *testing.T) {
+	url := testbus.URL(t)
+	open := aMesh(t)
+	js, err := broker.Dial(url)
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(js.Close)
+	for _, s := range []string{"CONTROL", "NODES", "ASSIGNMENTS", "EVENTS"} {
+		_ = js.Context().DeleteStream(s)
+	}
+	// The controller starting, before either was assigned.
+	if _, err := assertBusObjects(t.Context(), open.inventory, js); err != nil {
+		t.Fatal(err)
+	}
+	consumer := aCarriedConsumer(t, open)
+	worker := aLateHolder(t, open)
+	_ = js.Context().DeleteConsumer(worker.Stream, worker.Name)
+	for _, c := range []broker.Consumer{consumer, worker} {
+		if _, err := js.Context().ConsumerInfo(c.Stream, c.Name); !errors.Is(err, nats.ErrConsumerNotFound) {
+			t.Fatalf("%s on %s exists before any send; the test proves nothing: %v", c.Name, c.Stream, err)
+		}
+	}
+
+	server := link.ConnectNats(js, nil, nil)
+	if err := (overTheBus{open: open, server: server}).grant(t.Context(), nil); err != nil {
+		t.Fatal(err)
+	}
+	for _, c := range []broker.Consumer{consumer, worker} {
+		if _, err := js.Context().ConsumerInfo(c.Stream, c.Name); err != nil {
+			t.Fatalf("%s on %s is not on the bus after a send: %v", c.Name, c.Stream, err)
+		}
+	}
+	if _, raised, _ := conditionsFrom.Get(t.Context(), "bus.objects.unasserted"); raised {
+		t.Fatal("a send that asserted everything raised a condition")
+	}
+}

cmd/mesh-controller/busy.go

@@ -0,0 +1,103 @@
+package main
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// A first-node gate waits for a busy container (novox/hq ADR 0335 §4).
+//
+// When a machine reports, on what the gate sent it, that a container of a judged module was left running
+// because it said busy, the judging has not started: the build is not yet what runs there. The walk says it
+// waits for a busy container on that machine, counts no pass and no bound, and starts the judging — its
+// Since — at the report that no longer lists the container waiting. The wait is the node-engine's, bounded
+// at 15 minutes; the controller's own bound (busyGateBound past the engine's) is for an engine that stopped
+// reporting while it waited, so no walk waits for ever. An engine older than the field never lists one, and
+// its gate starts as before.
+
+// busyGateSlack is how long past the engine's bound the controller still waits for the report that says the
+// container replaced: a pass of the engine (its asks every 20 seconds) and the report's way here.
+var busyGateSlack = 5 * time.Minute
+
+// busyEngineBound is the node-engine's bound on a wait (novox/hq ADR 0335 §3), counted again here on this
+// controller's clock from when it first read the wait.
+const busyEngineBound = 15 * time.Minute
+
+// busyGateEnds is when the gate stops waiting: the engine's own word on its bound, or this controller's count of
+// it from when it first read the wait, whichever is sooner, and the slack — so neither a clock ahead on the
+// machine nor a wrong word from it holds a walk longer.
+func busyGateEnds(b *inventory.GateBusy) time.Time {
+	until := b.Seen.Add(busyEngineBound)
+	if !b.Until.IsZero() && b.Until.Before(until) {
+		until = b.Until
+	}
+	return until.Add(busyGateSlack)
+}
+
+// busyWait decides, before a judging, whether the gate waits for a busy container on a machine it judges:
+// true while it waits, the gate saying so. False when nothing waits, or no longer: a wait that ended moves the
+// gate's Since to its end. Pure but for the gate it is handed.
+func busyWait(g *inventory.PlanGate, pairs []judged, f gateFacts, now time.Time) bool {
+	if g.Busy != nil && g.Busy.Ended != nil {
+		return false
+	}
+	for _, j := range pairs {
+		b, waits := busyOn(j, f)
+		if !waits {
+			continue
+		}
+		if g.Busy == nil {
+			g.Busy = &inventory.GateBusy{Machine: j.node, Module: j.module, Container: b.Container, Since: b.Since,
+				Seen: now}
+		}
+		if g.Busy.Seen.IsZero() {
+			g.Busy.Seen = now
+		}
+		g.Busy.Until, g.Busy.Said = b.Until, b.Said
+		if now.After(busyGateEnds(g.Busy)) {
+			// The engine said it would have replaced it by now: the judging starts, and finds the module not
+			// yet healthy while the machine still lists it waiting (busyStill), until the gate's own bound.
+			end := now
+			g.Busy.Ended, g.Busy.PastBound = &end, true
+			g.Since, g.Passes, g.LastPass, g.Healthy, g.HealthyAt, g.Applied = &end, 0, nil, nil, nil, nil
+			return false
+		}
+		g.Passes, g.LastPass, g.Last, g.Failing = 0, nil, g.Busy.Words(), nil
+		g.Read(now, false, g.Busy.Words())
+		return true
+	}
+	if g.Busy == nil {
+		return false
+	}
+	// Replaced: the judging starts at the report that said so.
+	end := now
+	if r, said := f.reports[g.Busy.Machine]; said && r.At != nil && r.At.After(g.Busy.Since) && r.At.Before(now) {
+		end = r.At.UTC()
+	}
+	g.Busy.Ended = &end
+	g.Since, g.Passes, g.LastPass, g.Last, g.Healthy, g.HealthyAt, g.Applied = &end, 0, nil, "", nil, nil, nil
+	return false
+}
+
+// busyOn is the container of a judged module its machine last reported, on what the gate sent it, as left
+// running because it said busy.
+func busyOn(j judged, f gateFacts) (inventory.BusyWait, bool) {
+	r, said := f.reports[j.node]
+	if !said || r.At == nil || !f.reportedOn(j.node, r) {
+		return inventory.BusyWait{}, false
+	}
+	return inventory.WaitingFor(r.Busy, j.module)
+}
+
+// busyStill is a judged module whose container its machine still lists waiting once the gate stopped waiting
+// for it: not yet what was sent, so not healthy, whatever its health says of the container still running.
+func busyStill(j judged, f gateFacts) (string, bool) {
+	b, waits := busyOn(j, f)
+	if !waits {
+		return "", false
+	}
+	return fmt.Sprintf("%s still runs its busy container %s, past its node-engine's bound of %s",
+		j.node, b.Container, b.Until.UTC().Format(time.RFC3339)), true
+}

cmd/mesh-controller/busy_test.go

@@ -0,0 +1,148 @@
+package main
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// A walk whose module's container waits as busy on its first machine says so, and starts that machine's
+// first-machine gate only once the machine reports the container replaced (novox/hq ADR 0335 §4).
+func TestAGateWaitsForABusyContainerAndStartsWhenItIsReplaced(t *testing.T) {
+	sent := time.Date(2026, 10, 13, 1, 0, 0, 0, time.UTC)
+	g := &inventory.PlanGate{Machines: []string{"novox"}, Since: &sent,
+		Sent: map[string]inventory.SentDeclaration{"novox": {Digest: "d1", Sequence: 7}}}
+	pairs := []judged{{module: "build-agent", node: "novox"}, {module: "mesh-controller", node: "novox"}}
+	reported := sent.Add(20 * time.Second)
+	waiting := []inventory.BusyWait{{ID: "build-agent.server", Container: "mesh-build-agent",
+		State: inventory.BusyWaiting, Since: reported, Until: reported.Add(15 * time.Minute),
+		Said: "busy: novox/mesh-controller (check of #280), in hand since 00:58:00Z"}}
+	facts := func(at time.Time, busy []inventory.BusyWait) gateFacts {
+		// As judgeMoves hands it: the report held against the gate's own send.
+		return gateFacts{sent: g.Sent, reports: map[string]inventory.Reported{"novox": {Node: "novox",
+			Outcome: inventory.OutcomeApplied, At: &at, Declared: "d1", ReportedSequence: 7, Busy: busy}}}
+	}
+
+	now := reported.Add(time.Minute)
+	if !busyWait(g, pairs, facts(reported, waiting), now) {
+		t.Fatal("a gate whose module's container waits as busy judged it")
+	}
+	if !g.Since.Equal(sent) || g.Busy == nil || g.Busy.Machine != "novox" || g.Busy.Ended != nil {
+		t.Fatalf("the gate does not keep the wait: %+v %+v", g.Since, g.Busy)
+	}
+	for _, said := range []string{gateLine(g), g.Last} {
+		if !strings.Contains(said, "waits for a busy container on novox") {
+			t.Errorf("the walk does not say it waits for a busy container there: %s", said)
+		}
+	}
+	if !strings.Contains(g.Last, "check of #280") {
+		t.Errorf("the wait does not say what the container holds: %s", g.Last)
+	}
+
+	// Ten minutes on, still busy, within the engine's bound: still waiting, nothing judged, no bound run.
+	now = reported.Add(10 * time.Minute)
+	if !busyWait(g, pairs, facts(reported.Add(9*time.Minute), waiting), now) || g.Passes != 0 {
+		t.Fatalf("the gate stopped waiting within the bound: %+v", g)
+	}
+
+	// The machine reports it replaced: the judging starts at that report.
+	replacedAt := reported.Add(12 * time.Minute)
+	now = replacedAt.Add(5 * time.Second)
+	replaced := []inventory.BusyWait{{ID: "build-agent.server", Container: "mesh-build-agent",
+		State: "replaced-when-idle", Since: reported, Until: reported.Add(15 * time.Minute)}}
+	if busyWait(g, pairs, facts(replacedAt, replaced), now) {
+		t.Fatal("the gate still waits after the container was replaced")
+	}
+	if g.Since == nil || !g.Since.Equal(replacedAt) || g.Busy.Ended == nil || !g.Busy.Ended.Equal(replacedAt) {
+		t.Fatalf("the gate does not start at the report that said it replaced: since %v, %+v", g.Since, g.Busy)
+	}
+	if strings.Contains(gateLine(g), "waits for a busy container") {
+		t.Errorf("a gate judging still says it waits: %s", gateLine(g))
+	}
+	// And a later report listing it waiting again does not hold a gate that started.
+	if busyWait(g, pairs, facts(now, waiting), now.Add(time.Minute)) {
+		t.Error("a gate that started waits again")
+	}
+}
+
+// An engine that stops reporting while it waits holds no walk for ever: past the engine's bound and the slack,
+// the judging starts, and finds the module not yet healthy while its container is still listed waiting.
+func TestAGateWaitsNoLongerThanTheEnginesBound(t *testing.T) {
+	sent := time.Date(2026, 10, 13, 1, 0, 0, 0, time.UTC)
+	g := &inventory.PlanGate{Machines: []string{"novox"}, Since: &sent}
+	pairs := []judged{{module: "build-agent", node: "novox"}}
+	waiting := []inventory.BusyWait{{ID: "build-agent.server", Container: "mesh-build-agent",
+		State: inventory.BusyWaiting, Since: sent, Until: sent.Add(15 * time.Minute)}}
+	f := gateFacts{reports: map[string]inventory.Reported{"novox": {Node: "novox", Outcome: inventory.OutcomeApplied,
+		At: &sent, Current: true, Busy: waiting}}}
+	now := sent.Add(15*time.Minute + busyGateSlack + time.Second)
+	if busyWait(g, pairs, f, now) {
+		t.Fatal("a gate waited past the engine's bound and the slack")
+	}
+	if !g.Busy.PastBound || !g.Since.Equal(now) {
+		t.Fatalf("the gate does not start, said past the bound: %+v %v", g.Busy, g.Since)
+	}
+	if why, still := busyStill(pairs[0], f); !still || !strings.Contains(why, "past its node-engine's bound") {
+		t.Fatalf("a module still running its busy container reads as what was sent: %q", why)
+	}
+}
+
+// A report from an engine older than the field lists nothing: the gate starts at the send, as before; and a
+// report not about the gate's send says nothing of it.
+func TestAGateOfAnEngineThatNeverWaitsStartsAsBefore(t *testing.T) {
+	sent := time.Date(2026, 10, 13, 1, 0, 0, 0, time.UTC)
+	g := &inventory.PlanGate{Machines: []string{"ace"}, Since: &sent,
+		Sent: map[string]inventory.SentDeclaration{"ace": {Digest: "d2", Sequence: 9}}}
+	pairs := []judged{{module: "build-agent", node: "ace"}}
+	at := sent.Add(time.Minute)
+	older := gateFacts{sent: g.Sent, reports: map[string]inventory.Reported{"ace": {Node: "ace", Outcome: inventory.OutcomeApplied,
+		At: &at, Declared: "d2", ReportedSequence: 9}}}
+	if busyWait(g, pairs, older, at) || g.Busy != nil || !g.Since.Equal(sent) {
+		t.Fatalf("a gate on an engine that never waits did not start at the send: %+v %v", g.Busy, g.Since)
+	}
+	elsewhere := gateFacts{sent: g.Sent, reports: map[string]inventory.Reported{"ace": {Node: "ace", Outcome: inventory.OutcomeApplied,
+		At: &at, Declared: "d1", ReportedSequence: 8, Busy: []inventory.BusyWait{{ID: "build-agent.server",
+			State: inventory.BusyWaiting, Until: at.Add(time.Hour)}}}}}
+	if busyWait(g, pairs, elsewhere, at) {
+		t.Fatal("a wait reported about an earlier declaration held the gate")
+	}
+}
+
+// The wait is bounded on this controller's clock: an engine whose clock runs an hour ahead, saying it waits until
+// then, holds the gate no longer than 15 minutes and the slack from when the controller first read the wait.
+func TestAGateWaitIsBoundedOnTheControllersClock(t *testing.T) {
+	seen := time.Date(2026, 10, 13, 1, 0, 0, 0, time.UTC)
+	g := &inventory.PlanGate{Machines: []string{"novox"}, Since: &seen}
+	pairs := []judged{{module: "build-agent", node: "novox"}}
+	ahead := seen.Add(time.Hour)
+	f := gateFacts{reports: map[string]inventory.Reported{"novox": {Node: "novox", Outcome: inventory.OutcomeApplied,
+		At: &seen, Current: true, Busy: []inventory.BusyWait{{ID: "build-agent.server", Container: "mesh-build-agent",
+			State: inventory.BusyWaiting, Since: ahead, Until: ahead.Add(15 * time.Minute)}}}}}
+	if !busyWait(g, pairs, f, seen) || !g.Busy.Seen.Equal(seen) {
+		t.Fatalf("the gate did not start waiting, seen now: %+v", g.Busy)
+	}
+	if !busyWait(g, pairs, f, seen.Add(15*time.Minute+busyGateSlack-time.Second)) {
+		t.Fatal("the gate stopped waiting within the bound on its own clock")
+	}
+	if busyWait(g, pairs, f, seen.Add(15*time.Minute+busyGateSlack+time.Second)) || !g.Busy.PastBound {
+		t.Fatalf("an engine's later word held the gate past the controller's bound: %+v", g.Busy)
+	}
+}
+
+// `plan` says, for a machine whose node-engine is older than the field, each container whose busy is not sent.
+func TestAPlanSaysABusyAnOlderEngineIsNotSent(t *testing.T) {
+	modules := []catalogue.Manifest{{Module: "build-agent", Resources: []map[string]any{
+		{"id": "server", "type": "container", "busy": map[string]any{"command": "mesh-builder busy"}},
+		{"id": "agent-env", "type": "file"}}}}
+	lines := busyNotSent(modules, false)
+	if len(lines) != 1 || !strings.Contains(lines[0], "build-agent.server declares busy") ||
+		!strings.Contains(lines[0], "replaced at once") {
+		t.Fatalf("the plan does not say the busy not sent: %v", lines)
+	}
+	if lines := busyNotSent(modules, true); len(lines) != 0 {
+		t.Fatalf("a busy sent is said as not sent: %v", lines)
+	}
+}

cmd/mesh-controller/calls_verb_integration_test.go

@@ -0,0 +1,36 @@
+//go:build integration
+
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"strings"
+	"testing"
+)
+
+func TestCallsIsServedAndSaysWhatItKeeps(t *testing.T) {
+	handlers, behind, err := seatToolHandlers()
+	if err != nil || len(behind) != 0 {
+		t.Fatalf("%v %v", behind, err)
+	}
+	calls, ok := handlers["calls"]
+	if !ok {
+		t.Fatal("calls is not served")
+	}
+	if _, err := calls(context.Background(), json.RawMessage(`{"node":"anchor"}`)); err == nil ||
+		!strings.Contains(err.Error(), `"node"`) {
+		t.Errorf("calls took an argument it does not declare: %v", err)
+	}
+	if _, err := calls(context.Background(), json.RawMessage(`{"call":"call-0-0"}`)); err == nil ||
+		!strings.Contains(err.Error(), "not across a restart") {
+		t.Errorf("an unknown call was not said plainly: %v", err)
+	}
+	got, err := calls(context.Background(), json.RawMessage(`{}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, listed := got.(map[string]any)["calls"]; !listed {
+		t.Errorf("calls answered %v", got)
+	}
+}

cmd/mesh-controller/calls_verb_test.go

@@ -0,0 +1,51 @@
+package main
+
+import (
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/broker"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// consoleWaits is how long the console waits for an answer (mesh-tools node-tools/internal/bus
+// RequestTimeout) — the shortest wait of a caller the mesh ships.
+const consoleWaits = 30 * time.Second
+
+// **A call's one answer is never later than its caller or the bus allow** (novox/hq issue 265): a
+// holder answers within AnswerWithin, which must be inside both the console's wait and the window the
+// bus gives an answer. Before, the console waited 30s, the bus 60s, and a push ran as long as it ran.
+func TestAVerbAnswersInsideEveryWaitOnIt(t *testing.T) {
+	if link.AnswerWithin >= consoleWaits/2 {
+		t.Errorf("a call answers within %s: not well inside the console's %s", link.AnswerWithin, consoleWaits)
+	}
+	if link.AnswerWithin >= broker.ResponseTTL {
+		t.Errorf("a call answers within %s, after the bus stops permitting an answer at %s", link.AnswerWithin, broker.ResponseTTL)
+	}
+}
+
+// A push — named or through command — answers before it runs: it sends the machine holding the bus
+// first, and the broker reloading its user list forgets the answer it was about to permit.
+func TestAPushAnswersBeforeItSends(t *testing.T) {
+	for _, c := range []struct {
+		verb string
+		args map[string]any
+		want bool
+	}{
+		{"push", map[string]any{"node": "anchor", "why": "w"}, true},
+		{"push", map[string]any{"why": "w"}, true},
+		{"command", map[string]any{"command": "builds"}, false},
+		{"status", map[string]any{}, false},
+		{"assign", map[string]any{"node": "anchor", "module": "m"}, false},
+	} {
+		argv, err := argvFor(c.verb, c.args)
+		if err != nil {
+			t.Fatalf("%s %v: %v", c.verb, c.args, err)
+		}
+		if got := answersFirst(argv); got != c.want {
+			t.Errorf("%s %v answers first: %v, want %v", c.verb, c.args, got, c.want)
+		}
+	}
+}
+
+// `calls` is served, takes a call's id and nothing else, and says plainly when it holds no such call.

cmd/mesh-controller/chain.go

@@ -0,0 +1,177 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/chain"
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// The chain on the bus (novox/hq ADR 0408, design 47 milestone 5): builds, rollouts and assignments are keys of the
+// bus's key-value store, written by the controller that holds the lease, and the controller's store keeps none of them.
+
+// chainHolds is whether this process may write the chain now: the lease's gate, the one every act passes.
+func chainHolds(ctx context.Context) error {
+	_, err := theLease.epoch(ctx)
+	return err
+}
+
+// openTheChain opens the chain's buckets on the bus: the serving controller's connection, or one dialled for a command.
+func openTheChain(ctx context.Context) (*chain.Chain, error) {
+	js, err := aBus()
+	if err != nil {
+		return nil, err
+	}
+	// Not closed: a borrowed connection closes nothing, and a dialled one lasts as long as the command.
+	return chain.OnTheBus(ctx, js.Conn(), chainHolds)
+}
+
+// attachTheChain gives the inventory of the serving controller the chain on its connection.
+func attachTheChain(ctx context.Context, inv *inventory.Inventory, server *link.Server) error {
+	bus, ok := server.Bus().(link.OverNATS)
+	if !ok {
+		return errors.New("the chain lives on the bus, and this control plane is not on it")
+	}
+	c, err := chain.OnTheBus(ctx, bus.Conn, chainHolds)
+	if err != nil {
+		return err
+	}
+	inv.UseChain(c)
+	inv.RequireLayout()
+	// And the builds laid out under their modules, once, before they are read (issue 1121) — **before this returns**, so
+	// nothing the start goes on to read meets a chain not laid out yet: on 2026-10-18 the layout ran beside the start, a
+	// read of the start was refused, and the controller exited and was started again every five seconds. The layout of
+	// keys laid out before skips them, so this takes seconds; one that fails is tried again beside the serving, loudly.
+	if err := inv.LayBuildsOut(ctx, func(format string, args ...any) { fmt.Printf("chain: "+format+"\n", args...) }); err != nil {
+		fmt.Printf("chain: the builds are not laid out under their modules yet, and none is read until they are: %v\n", err)
+		go layBuildsOutSoon(ctx, inv)
+	}
+	// And the requests the move of delivery 1 found never handed over, asked again once (askAgain), once it is serving.
+	go askAgainSoon(ctx, inv)
+	// And what delivery 1 recorded of what each machine was sent, copied onto the keys of the assignments (CopySentBuilds).
+	go copySentBuildsSoon(ctx, inv)
+	return nil
+}
+
+// askAgain asks once more for each build request the move found never handed over (novox/hq issue 981 note 7 Q5): the
+// requests a merge could not ask for, which a person's hand `build` would otherwise have to repeat. **At most once**: a
+// request is claimed before it is asked and settled after, so a crash between loses the ask, which is where it stood.
+func askAgain(ctx context.Context, inv *inventory.Inventory) {
+	pending, err := inv.RequestsToAskAgain(ctx)
+	if err != nil {
+		fmt.Printf("chain: the requests never handed over cannot be read: %v\n", err)
+		return
+	}
+	for _, r := range pending {
+		if claimed, err := inv.ClaimToAskAgain(ctx, r.ID); err != nil || !claimed {
+			if err != nil {
+				fmt.Printf("chain: %s cannot be claimed to be asked again: %v\n", r.ID, err)
+			}
+			continue
+		}
+		id, err := askABuild(ctx, buildSource{Repository: r.Repository, Seat: r.Seat}, r.Path, r.Ref)
+		if err != nil {
+			if serr := inv.AskedAgainAs(ctx, r.ID, "not asked again: "+err.Error()); serr != nil {
+				fmt.Printf("chain: %s was not asked again, and that could not be kept: %v\n", r.ID, serr)
+			}
+			fmt.Printf("chain: %s was never handed over and cannot be asked again: %v\n", r.ID, err)
+			continue
+		}
+		recordBuildRequest(ctx, inv, inventory.BuildRequest{ID: id, Repository: r.Repository, Seat: r.Seat, Path: r.Path,
+			Ref: r.Ref, Commit: r.Commit, For: r.For})
+		if err := inv.AskedAgainAs(ctx, r.ID, id); err != nil {
+			fmt.Printf("chain: %s was asked again as %s, and that could not be kept: %v\n", r.ID, id, err)
+		}
+		fmt.Printf("chain: %s, never handed over, is asked again as %s\n", r.ID, id)
+	}
+}
+
+// askAgainSoon waits for the controller to be serving, which an ask needs, and then asks again.
+func askAgainSoon(ctx context.Context, inv *inventory.Inventory) {
+	select {
+	case <-ctx.Done():
+	case <-time.After(time.Minute):
+		askAgain(ctx, inv)
+	}
+}
+
+// kindSentBuildsNotCopied is the condition of the one-time copy of node.sent_builds onto the assignments' keys that has not
+// succeeded: until it has, a module an assignment pulled in may be missing from what a machine is read to run.
+const kindSentBuildsNotCopied = "sent-builds-not-copied"
+
+// copySentBuildsSoon copies what the store recorded of what each machine was sent onto the keys of the assignments, as soon
+// as this controller holds the lease (the chain refuses a write before), and tries again every half minute while it fails,
+// each time it fails saying so as an urgent condition until it has worked. It is idempotent: CopySentBuilds overwrites no key
+// that names a commit and empties each column it has copied.
+func copySentBuildsSoon(ctx context.Context, inv *inventory.Inventory) {
+	failed := false
+	for {
+		_, err := inv.CopySentBuilds(ctx)
+		o := conditions.Observation{Scope: conditions.ScopeBuild, ID: kindSentBuildsNotCopied, Token: kindSentBuildsNotCopied,
+			Kind: kindSentBuildsNotCopied, Severity: conditions.Urgent, Resolver: conditions.ResolverOperator,
+			Source: "chain", Summary: "what each machine was sent is not copied onto its assignments: "}
+		if err != nil {
+			fmt.Printf("chain: what the machines were sent is not copied onto the assignments: %v\n", err)
+			if keeper := conditionsFrom; keeper != nil && !failed {
+				o.Summary += err.Error()
+				if _, oerr := keeper.Observe(ctx, o); oerr == nil {
+					failed = true
+				}
+			}
+		} else {
+			if keeper := conditionsFrom; keeper != nil && failed {
+				_, _ = keeper.Clear(ctx, o.Key(), "copied")
+			}
+			return
+		}
+		select {
+		case <-ctx.Done():
+			return
+		case <-time.After(chainMoveRetry):
+		}
+	}
+}
+
+// chainMoveRetry is how long the copy waits before it tries again.
+const chainMoveRetry = 30 * time.Second
+
+// kindBuildsNotLaidOut is the condition of the layout of the builds under their modules that has not succeeded: until it
+// has, no build is read, and a send that needs one is refused with the reason.
+const kindBuildsNotLaidOut = "builds-not-laid-out"
+
+// layBuildsOutSoon lays the builds out under their modules as soon as this controller holds the lease (the chain refuses a
+// write before), and tries again every half minute while it fails, loudly: each failure is printed, and the first raises an
+// urgent condition until it has worked. It is idempotent (LayBuildsOut).
+func layBuildsOutSoon(ctx context.Context, inv *inventory.Inventory) {
+	failed := false
+	for {
+		err := inv.LayBuildsOut(ctx, func(format string, args ...any) { fmt.Printf("chain: "+format+"\n", args...) })
+		o := conditions.Observation{Scope: conditions.ScopeBuild, ID: kindBuildsNotLaidOut, Token: kindBuildsNotLaidOut,
+			Kind: kindBuildsNotLaidOut, Severity: conditions.Urgent, Resolver: conditions.ResolverOperator,
+			Source: "chain", Summary: "the builds are not laid out under their modules, so none is read: "}
+		if err != nil {
+			fmt.Printf("chain: the builds are not laid out under their modules, and none is read until they are: %v\n", err)
+			if keeper := conditionsFrom; keeper != nil && !failed {
+				o.Summary += err.Error()
+				if _, oerr := keeper.Observe(ctx, o); oerr == nil {
+					failed = true
+				}
+			}
+		} else {
+			if keeper := conditionsFrom; keeper != nil && failed {
+				_, _ = keeper.Clear(ctx, o.Key(), "laid out")
+			}
+			return
+		}
+		select {
+		case <-ctx.Done():
+			return
+		case <-time.After(chainMoveRetry):
+		}
+	}
+}

cmd/mesh-controller/chain_integration_test.go

@@ -0,0 +1,245 @@
+//go:build integration
+
+package main
+
+import (
+	"context"
+	"fmt"
+	"slices"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/chain"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/lease"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// **Acceptance 10 of design 47: one read of an assignment names the commit, the build and the rollout that put it there,
+// and one read of the rollout lists the assignments it changed** (novox/hq ADR 0408, issue 1095). It enters by the live
+// trigger — a merge heard, its batch cut into a plan when the window closed, its build answered through the build seat's
+// path, the plan advanced — and writes no key and no row by hand. Only the machine's end of the send is the test's: the send
+// is recorded as the controller records one it made, and the gate's facts are the store's.
+func TestOneReadOfAnAssignmentNamesItsCommitBuildAndRolloutAndOneReadOfTheRolloutListsItsAssignments(t *testing.T) {
+	open := windowed(t)
+	everyHeadWaits(t)
+	asked := asksRecorded(t)
+	ctx := t.Context()
+	inv := open.inventory
+	if _, err := assign(ctx, open, "anchor", "notes"); err != nil {
+		t.Fatal(err)
+	}
+
+	var sent [][]string
+	wasSend := sendRollout
+	sendRollout = func(ctx context.Context, open *stores, names []string) ([]string, error) {
+		sent = append(sent, append([]string(nil), names...))
+		current, err := open.inventory.CurrentBuilds(ctx)
+		if err != nil {
+			return nil, err
+		}
+		for _, node := range names {
+			digest := fmt.Sprintf("d-%s-%d", node, len(sent))
+			if err := open.inventory.RecordSent(ctx, nodeID(t, open, node), digest,
+				map[string]string{"notes": current["notes"].Commit}); err != nil {
+				return nil, err
+			}
+		}
+		return names, nil
+	}
+	t.Cleanup(func() { sendRollout = wasSend })
+	wasGather := gatherGateFacts
+	gatherGateFacts = func(ctx context.Context, open *stores, component string) (gateFacts, error) {
+		f := gateFacts{now: time.Now(), reports: map[string]inventory.Reported{}, engines: map[string]string{},
+			rolledBack: map[string][]lease.Rollback{}, served: map[string]served{}}
+		reports, err := open.inventory.LastReports(ctx)
+		if err != nil {
+			return f, err
+		}
+		for _, r := range reports {
+			f.reports[r.Node] = r
+		}
+		return f, nil
+	}
+	t.Cleanup(func() { gatherGateFacts = wasGather })
+
+	// A merge of notes is heard, and its window closes: the batch is cut into the walk.
+	hear(t, open, catalogueMerge("c-notes", "notes", t0), t0.Add(time.Second))
+	cutAt(t, open, t0.Add(time.Second+90*time.Second))
+	ws, _ := walks(t, open)
+	if len(ws) != 1 {
+		t.Fatalf("%d walk(s) after the cut", len(ws))
+	}
+	rollout := ws[0].ID
+
+	// The walk asks its first tier (at the cut, or at its next step); the build seat answers, and the controller takes the
+	// outcome in as it does.
+	asking, err := inv.PlanByID(ctx, rollout)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for try := 0; try < 3 && (asking.Modules["notes"] == nil || asking.Modules["notes"].Build == ""); try++ {
+		advancePlans(ctx, open)
+		if asking, err = inv.PlanByID(ctx, rollout); err != nil {
+			t.Fatal(err)
+		}
+	}
+	buildID := asking.Modules["notes"].Build
+	if buildID == "" || len(*asked) != 1 || !strings.HasSuffix((*asked)[0], "#"+buildID) {
+		t.Fatalf("the walk asked %v, and notes' build is %q", *asked, buildID)
+	}
+	digest := "sha256:" + strings.Repeat("a", 64)
+	result := outcome(buildID, "modules/notes", "c-notes", "notes", "")
+	result.ReuseKey = "rk-notes"
+	result.Made = []link.MadeArtifact{{Name: "notes", Kind: "image", Reference: "artifact-store://notes/notes@" + digest}}
+	if err := (builds{inv: inv, open: open}).Built(ctx, result); err != nil {
+		t.Fatal(err)
+	}
+
+	// The walk sends the tier to its first machine.
+	for try := 0; try < 3 && len(sent) == 0; try++ {
+		advancePlans(ctx, open)
+	}
+	if !slices.Equal(slices.Concat(sent...), []string{"anchor"}) {
+		t.Fatalf("sent %v", sent)
+	}
+
+	// One read of the assignment.
+	on, err := inv.AssignmentsOn(ctx, "anchor")
+	a, ok := assignmentOf(on, "notes")
+	if err != nil || !ok {
+		t.Fatalf("the assignments of anchor: %+v %v", on, err)
+	}
+	// Beside it a module pulled in by the assignment, which no send of this walk put anywhere.
+	if wireguard, pulled := assignmentOf(on, "mesh-wireguard"); pulled && (wireguard.Build != "" || wireguard.Rollout != "") {
+		t.Fatalf("a module this rollout did not send names a build or a rollout: %+v", wireguard)
+	}
+	if a.Module != "notes" || a.Commit != "c-notes" || a.Build != buildID || a.Rollout != rollout || a.Artifact != digest ||
+		a.Since.IsZero() || a.Assigned.IsZero() || !a.Stands() {
+		t.Fatalf("the assignment names %+v, not commit c-notes, build %s, artifact %s, rollout %s", a, buildID, digest, rollout)
+	}
+	// One read of the rollout.
+	p, err := inv.PlanByID(ctx, rollout)
+	if err != nil {
+		t.Fatal(err)
+	}
+	wantChange := chain.Change{Node: "anchor", Module: "notes", After: chain.Ref{Build: buildID, Commit: "c-notes"}}
+	if !slices.Contains(p.Changed, wantChange) || !slices.Contains(p.Builds, buildID) || len(p.Steps) != 1 ||
+		p.Steps[0].Node != "anchor" || p.Steps[0].Sent == nil {
+		t.Fatalf("the rollout lists changed %+v, builds %v, steps %+v; want %+v", p.Changed, p.Builds, p.Steps, wantChange)
+	}
+	// And one read of the build names the same commit, with what it published and its reuse key.
+	built, found, err := inv.BuildByID(ctx, buildID)
+	if err != nil || !found || built.Commit != "c-notes" || built.Module != "notes" {
+		t.Fatalf("the build: %+v %v %v", built, found, err)
+	}
+	lately, err := inv.Builds(ctx, "notes", 1)
+	if err != nil || len(lately) != 1 || lately[0].ReuseKey != "rk-notes" || lately[0].Published == nil ||
+		lately[0].Published.Artifact != digest {
+		t.Fatalf("what the build published: %+v %v", lately, err)
+	}
+	// The verbs say the links.
+	if lines := changedLines(p); len(lines) != 2 || !strings.Contains(lines[1], "anchor/notes") ||
+		!strings.Contains(lines[1], buildID) {
+		t.Fatalf("`plans` says %v", lines)
+	}
+	if lines := runLines(on); len(lines) != 2 || !strings.Contains(lines[1], buildID) || !strings.Contains(lines[1], rollout) {
+		t.Fatalf("`node show` says %v", lines)
+	}
+}
+
+// A machine sent again what it runs says nothing new, and a push by hand with no rollout fills what is missing and blanks
+// nothing (issue 1095).
+func TestASendOfWhatAMachineRunsAlreadyChangesNoLinkOfItsAssignment(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	inv := open.inventory
+	register(t, open, catalogue.Manifest{Module: "notes", Version: "1"})
+	if _, err := assign(ctx, open, "anchor", "notes"); err != nil {
+		t.Fatal(err)
+	}
+	if err := inv.RecordBuild(ctx, inventory.Build{ID: "build-1", Module: "notes", Commit: "c1", Repository: "novox/notes"}); err != nil {
+		t.Fatal(err)
+	}
+	node := nodeID(t, open, "anchor")
+	inRollout := inventory.WithRollout(ctx, "plan-1", map[string]inventory.RolloutModule{"notes": {Commit: "c1", Build: "build-1"}})
+	if err := inv.RecordSent(inRollout, node, "d1", map[string]string{"notes": "c1"}); err != nil {
+		t.Fatal(err)
+	}
+	// Sent again by hand, with no rollout: the assignment still names the rollout that put the build there.
+	if err := inv.RecordSent(ctx, node, "d2", map[string]string{"notes": "c1"}); err != nil {
+		t.Fatal(err)
+	}
+	on, _ := inv.AssignmentsOn(ctx, "anchor")
+	if a, _ := assignmentOf(on, "notes"); a.Rollout != "plan-1" || a.Build != "build-1" || a.Commit != "c1" {
+		t.Fatalf("the assignment names %+v", on)
+	}
+	// A declaration sent by hand with no builds known makes what the machine runs unknown: a time on the key, no commit.
+	if err := inv.RecordSent(ctx, node, "d3", nil); err != nil {
+		t.Fatal(err)
+	}
+	if on, _ = inv.AssignmentsOn(ctx, "anchor"); runOf(on, "notes").Commit != "" || runOf(on, "notes").SentUnknown.IsZero() {
+		t.Fatalf("a send of unknown builds left %+v", on)
+	}
+	// A module sent a commit no build is kept of is named by its commit alone.
+	if err := inv.RecordSent(ctx, node, "d4", map[string]string{"notes": "c2"}); err != nil {
+		t.Fatal(err)
+	}
+	if on, _ = inv.AssignmentsOn(ctx, "anchor"); runOf(on, "notes").Commit != "c2" || runOf(on, "notes").Build != "" ||
+		runOf(on, "notes").Rollout != "" {
+		t.Fatalf("the assignment after a push of c2 by hand names %+v", on)
+	}
+}
+
+// assignmentOf is one module's assignment among those of a machine: assigning a module assigns what it requires beside it.
+func assignmentOf(on []chain.Assignment, module string) (chain.Assignment, bool) {
+	for _, a := range on {
+		if a.Module == module {
+			return a, true
+		}
+	}
+	return chain.Assignment{}, false
+}
+
+func runOf(on []chain.Assignment, module string) chain.Assignment {
+	a, _ := assignmentOf(on, module)
+	return a
+}
+
+// **An assignment waiting for its build is one key of the assignments bucket** (ADR 0261, ADR 0408, issue 1094): entered
+// through the `assign` verb for a module whose build is in flight, one read of `<node>.<module>` says state pending with the
+// build it waits for, the build's outcome through the build seat's path makes the key stand with the wait carried as applied,
+// and the table of pending assignments is read by nobody. No key is written by hand.
+func TestAnAssignmentWaitingForItsBuildIsOneKeyOfTheAssignmentsBucket(t *testing.T) {
+	open := aCatalogueMesh(t)
+	ctx := t.Context()
+	inv := open.inventory
+	asksWithPaths(t)
+	mergeAdding(t, open, "modules/sensors", "3da80a4b00aa")
+	if _, err := assign(ctx, open, "laptop", "sensors"); err != nil {
+		t.Fatalf("an assignment while its build runs was refused: %v", err)
+	}
+	waiting, found, err := inv.AssignmentValue(ctx, "laptop", "sensors")
+	if err != nil || !found || waiting.State != chain.StatePending || waiting.Stands() || !waiting.Assigned.IsZero() ||
+		waiting.Pending == nil || waiting.Pending.State != chain.PendingWaiting || waiting.Pending.Build != "b-modules/sensors" ||
+		!strings.HasPrefix(waiting.Pending.ID, "p-") {
+		t.Fatalf("one read of the key says %+v (found %v, %v)", waiting, found, err)
+	}
+	if got := assignedTo(t, open, "laptop"); slices.Contains(got, "sensors") {
+		t.Fatalf("a module only waiting is assigned: %v", got)
+	}
+
+	if err := (builds{inv: inv, open: open}).Built(ctx, outcome("b-modules/sensors", "modules/sensors", "3da80a4b00aa", "sensors", "")); err != nil {
+		t.Fatal(err)
+	}
+	made, found, err := inv.AssignmentValue(ctx, "laptop", "sensors")
+	if err != nil || !found || !made.Stands() || made.State != "" || made.Assigned.IsZero() || made.Pending == nil ||
+		made.Pending.State != chain.PendingApplied || made.Pending.ID != waiting.Pending.ID {
+		t.Fatalf("one read of the key after the build says %+v (found %v, %v)", made, found, err)
+	}
+	if !slices.Contains(assignedTo(t, open, "laptop"), "sensors") {
+		t.Fatal("the build registered sensors and it was not assigned")
+	}
+}

cmd/mesh-controller/chain_links.go

@@ -0,0 +1,121 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"slices"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/chain"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// The links a rollout makes (novox/hq ADR 0408 §1, design 47 acceptance 10, issue 1095): the send of a plan's tier puts a
+// build on a machine; the assignment of the module there names the build, its commit and the rollout (written by the record of
+// the send, inventory.RecordSent, from the context a send is made in), and the rollout lists the assignments it changed with the
+// build before and after.
+
+// rolloutModules is what a plan sends of each module: the commit and the build of it.
+func rolloutModules(p *inventory.Plan) map[string]inventory.RolloutModule {
+	out := make(map[string]inventory.RolloutModule, len(p.Modules))
+	for m, s := range p.Modules {
+		if s != nil && s.Commit != "" {
+			out[m] = inventory.RolloutModule{Commit: s.Commit, Build: s.Build}
+		}
+	}
+	return out
+}
+
+// sendingAs is the context a plan's send is made in: what is recorded of the send names this rollout.
+func sendingAs(ctx context.Context, p *inventory.Plan) context.Context {
+	return inventory.WithRollout(ctx, p.ID, rolloutModules(p))
+}
+
+// ranBefore is what each module on a machine ran before a send, as the chain names it: its assignment's build and commit,
+// else the commit the machine was last sent for it. Read before the send, which writes the new ones.
+func ranBefore(ctx context.Context, inv *inventory.Inventory, node string) map[string]chain.Ref {
+	was := map[string]chain.Ref{}
+	if sent, known, err := inv.SentBuilds(ctx, node); err == nil && known {
+		for m, commit := range sent {
+			was[m] = chain.Ref{Commit: commit}
+		}
+	}
+	if ran, err := inv.AssignmentRuns(ctx, node); err == nil {
+		for m, r := range ran {
+			was[m] = r
+		}
+	}
+	return was
+}
+
+// noteChanges writes into a plan that a send to a machine changed the assignments of the modules it carried: the build and
+// commit before and after, the builds the rollout carried, and the step taken. A change noted already for the machine and the
+// module is replaced, so a send made again says it once.
+func noteChanges(p *inventory.Plan, node string, modules []string, was map[string]chain.Ref, at time.Time) {
+	for _, m := range modules {
+		s := p.Modules[m]
+		if s == nil {
+			continue
+		}
+		change := chain.Change{Node: node, Module: m, Before: was[m], After: chain.Ref{Build: s.Build, Commit: s.Commit}}
+		if at := slices.IndexFunc(p.Changed, func(c chain.Change) bool { return c.Node == node && c.Module == m }); at >= 0 {
+			change.Before = p.Changed[at].Before
+			p.Changed[at] = change
+		} else {
+			p.Changed = append(p.Changed, change)
+		}
+		if s.Build != "" && !slices.Contains(p.Builds, s.Build) {
+			p.Builds = append(p.Builds, s.Build)
+		}
+	}
+	if !slices.ContainsFunc(p.Steps, func(s chain.Step) bool { return s.Tier == p.Tier && s.Node == node }) {
+		sent := at.UTC()
+		p.Steps = append(p.Steps, chain.Step{Tier: p.Tier, Node: node, Sent: &sent})
+	}
+}
+
+// refSaid is a build and the commit it was made from as a person reads them; "nothing" for a module that ran none.
+func refSaid(r chain.Ref) string {
+	switch {
+	case r.Build == "" && r.Commit == "":
+		return "nothing"
+	case r.Build == "":
+		return "commit " + short(r.Commit)
+	}
+	return r.Build + " (" + short(r.Commit) + ")"
+}
+
+// changedLines say the assignments a rollout changed: the machine, the module, and the build before and after.
+func changedLines(p inventory.Plan) []string {
+	if len(p.Changed) == 0 {
+		return nil
+	}
+	out := []string{"  changed:"}
+	for _, c := range p.Changed {
+		out = append(out, fmt.Sprintf("    %s/%s  %s → %s", c.Node, c.Module, refSaid(c.Before), refSaid(c.After)))
+	}
+	return out
+}
+
+// runLines say what each module assigned to a machine runs there, as its assignment names it: the build, the commit, the
+// rollout that put it there and since when.
+func runLines(assigned []chain.Assignment) []string {
+	var out []string
+	for _, a := range assigned {
+		if a.Build == "" && a.Commit == "" {
+			continue
+		}
+		line := fmt.Sprintf("    %-22s %s", a.Module, refSaid(chain.Ref{Build: a.Build, Commit: a.Commit}))
+		if a.Rollout != "" {
+			line += ", sent by " + a.Rollout
+		}
+		if !a.Since.IsZero() {
+			line += " at " + a.Since.Local().Format("2006-01-02 15:04")
+		}
+		out = append(out, line)
+	}
+	if len(out) == 0 {
+		return nil
+	}
+	return append([]string{"  what they run, as the chain names it:"}, out...)
+}

cmd/mesh-controller/chain_links_test.go

@@ -0,0 +1,69 @@
+package main
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/chain"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// **A rollout lists the assignments it changed, each with the build before and after** (ADR 0408 §1, issue 1095): one
+// change for a machine and a module however often the send is noted, the build before kept from the first, the builds the
+// rollout carried once each, and one step for a machine and a tier.
+func TestARolloutListsTheAssignmentsItChangedWithTheBuildBeforeAndAfter(t *testing.T) {
+	at := time.Date(2026, 10, 18, 3, 0, 0, 0, time.UTC)
+	p := inventory.Plan{ID: "plan-1", Tier: 1, Modules: map[string]*inventory.PlanModule{
+		"notes": {Commit: "c2", Build: "b2"}, "wiki": {Commit: "c2w", Build: "b2w"}, "nothing": nil}}
+	was := map[string]chain.Ref{"notes": {Build: "b1", Commit: "c1"}, "wiki": {Commit: "c1w"}}
+
+	noteChanges(&p, "anchor", []string{"notes", "wiki", "nothing"}, was, at)
+	noteChanges(&p, "laptop", []string{"notes"}, nil, at)
+	// The send noted again, after what was sent had become what the machine runs: the first before stands.
+	noteChanges(&p, "anchor", []string{"notes"}, map[string]chain.Ref{"notes": {Build: "b2", Commit: "c2"}}, at.Add(time.Minute))
+
+	want := []chain.Change{
+		{Node: "anchor", Module: "notes", Before: chain.Ref{Build: "b1", Commit: "c1"}, After: chain.Ref{Build: "b2", Commit: "c2"}},
+		{Node: "anchor", Module: "wiki", Before: chain.Ref{Commit: "c1w"}, After: chain.Ref{Build: "b2w", Commit: "c2w"}},
+		{Node: "laptop", Module: "notes", After: chain.Ref{Build: "b2", Commit: "c2"}},
+	}
+	if len(p.Changed) != len(want) {
+		t.Fatalf("changed %+v", p.Changed)
+	}
+	for k := range want {
+		if p.Changed[k] != want[k] {
+			t.Errorf("change %d is %+v, want %+v", k, p.Changed[k], want[k])
+		}
+	}
+	if len(p.Builds) != 2 || p.Builds[0] != "b2" || p.Builds[1] != "b2w" {
+		t.Errorf("builds %v", p.Builds)
+	}
+	if len(p.Steps) != 2 || p.Steps[0].Node != "anchor" || p.Steps[0].Tier != 1 || p.Steps[0].Sent == nil || p.Steps[1].Node != "laptop" {
+		t.Errorf("steps %+v", p.Steps)
+	}
+	lines := changedLines(p)
+	if len(lines) != 4 || !strings.Contains(lines[1], "anchor/notes  b1 (c1) → b2 (c2)") ||
+		!strings.Contains(lines[3], "laptop/notes  nothing → b2 (c2)") {
+		t.Errorf("changed lines %q", lines)
+	}
+	if got := changedLines(inventory.Plan{}); got != nil {
+		t.Errorf("a plan that changed nothing says %q", got)
+	}
+}
+
+func TestWhatAMachineRunsIsSaidAsItsAssignmentNamesIt(t *testing.T) {
+	at := time.Date(2026, 10, 18, 3, 0, 0, 0, time.UTC)
+	lines := runLines([]chain.Assignment{
+		{Node: "anchor", Module: "notes", Build: "b2", Commit: "c2c2c2c2c2c2", Rollout: "plan-1", Since: at},
+		{Node: "anchor", Module: "web", Commit: "c3"},
+		{Node: "anchor", Module: "never-sent"},
+	})
+	if len(lines) != 3 || !strings.Contains(lines[1], "notes") || !strings.Contains(lines[1], "b2 (c2c2c2c2)") ||
+		!strings.Contains(lines[1], "sent by plan-1") || !strings.Contains(lines[2], "web") || !strings.Contains(lines[2], "commit c3") {
+		t.Fatalf("lines %q", lines)
+	}
+	if runLines([]chain.Assignment{{Node: "a", Module: "m"}}) != nil {
+		t.Fatal("a module never sent is said to run something")
+	}
+}

cmd/mesh-controller/chain_no_table_integration_test.go

@@ -0,0 +1,85 @@
+//go:build integration
+
+package main
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// **Acceptance 12 of design 47: no table in the controller's store holds builds, rollouts or assignments** (novox/hq ADR
+// 0408, issue 1111). A delivery is driven through the live trigger — a merge heard, its batch cut into a plan, the plan's
+// build asked and answered, the assignment made — until a build, a rollout and an assignment exist; they are read from the
+// chain, and then the store's own catalog is read: none of the tables of the chain is in it, nor the function that raised the generation from the assignment table; the table that stays, stays.
+func TestNoTableOfTheControllersStoreHoldsBuildsRolloutsOrAssignments(t *testing.T) {
+	open := windowed(t)
+	everyHeadWaits(t)
+	asked := asksRecorded(t)
+	ctx := t.Context()
+	inv := open.inventory
+	if _, err := assign(ctx, open, "anchor", "notes"); err != nil {
+		t.Fatal(err)
+	}
+	hear(t, open, catalogueMerge("c-notes", "notes", t0), t0.Add(time.Second))
+	cutAt(t, open, t0.Add(91*time.Second))
+	ws, _ := walks(t, open)
+	if len(ws) != 1 {
+		t.Fatalf("%d walk(s) after the cut", len(ws))
+	}
+	rollout := ws[0].ID
+	asking, err := inv.PlanByID(ctx, rollout)
+	if err != nil {
+		t.Fatal(err)
+	}
+	for try := 0; try < 3 && (asking.Modules["notes"] == nil || asking.Modules["notes"].Build == ""); try++ {
+		advancePlans(ctx, open)
+		if asking, err = inv.PlanByID(ctx, rollout); err != nil {
+			t.Fatal(err)
+		}
+	}
+	buildID := asking.Modules["notes"].Build
+	if buildID == "" || len(*asked) != 1 {
+		t.Fatalf("the walk asked %v, and notes' build is %q", *asked, buildID)
+	}
+	digest := "sha256:" + strings.Repeat("b", 64)
+	result := outcome(buildID, "modules/notes", "c-notes", "notes", "")
+	result.Made = []link.MadeArtifact{{Name: "notes", Kind: "image", Reference: "artifact-store://notes/notes@" + digest}}
+	if err := (builds{inv: inv, open: open}).Built(ctx, result); err != nil {
+		t.Fatal(err)
+	}
+
+	// What the live path made is in the chain.
+	if built, found, err := inv.BuildByID(ctx, buildID); err != nil || !found || built.Commit != "c-notes" {
+		t.Fatalf("the build is not read from the chain: %+v %v %v", built, found, err)
+	}
+	if p, err := inv.PlanByID(ctx, rollout); err != nil || p.ID != rollout {
+		t.Fatalf("the rollout is not read from the chain: %+v %v", p, err)
+	}
+	if on, err := inv.AssignmentsOn(ctx, "anchor"); err != nil {
+		t.Fatal(err)
+	} else if _, ok := assignmentOf(on, "notes"); !ok {
+		t.Fatalf("the assignment is not read from the chain: %+v", on)
+	}
+
+	// And the catalog of the store holds none of them.
+	have := map[string]bool{}
+	for _, row := range inv.QueryForTest(t, `select table_name::text from information_schema.tables where table_schema = 'public'`) {
+		have[strings.Trim(row[0], `"`)] = true
+	}
+	for _, table := range []string{"build", "build_request", "release_plan", "batched_merge", "assignment", "pending_assignment", "chain_moved"} {
+		if have[table] {
+			t.Errorf("the table %s is in the controller's store", table)
+		}
+	}
+	for _, table := range []string{"build_gate", "assignment_generation"} {
+		if !have[table] {
+			t.Errorf("the table %s, which stays, is gone", table)
+		}
+	}
+	if rows := inv.QueryForTest(t, `select count(*) from pg_proc where proname = 'raise_assignment_generation'`); rows[0][0] != "0" {
+		t.Errorf("the function raise_assignment_generation is in the store: %v", rows)
+	}
+}

cmd/mesh-controller/changeplan.go

@@ -0,0 +1,221 @@
+package main
+
+import (
+	"fmt"
+	"path"
+	"slices"
+	"sort"
+	"strings"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// The change plan (novox/hq ADR 0238): **one commit, one plan** — what a change does to the mesh, computed
+// from its diffset (a repository, the branch it merges into, the commit at hand) by the planner, never by
+// a mapping of its own. reachOfMerge answers what moves and what follows it; this adds where each module
+// goes — the deploy plan, machine by machine in the build plan's order — and what is not an ordinary
+// send. A pull request's check posts it with its verdict; the release a merge makes follows the same
+// planner, so the two can be compared.
+
+// policyOf is a module's upgrade policy, as the controller holds it; false when it cannot be read.
+type policyOf func(module string) (inventory.Upgrade, bool)
+
+// changePlanOf is the change plan of a reach: pure, so it is tested without a store.
+func changePlanOf(repository, base, head string, r mergeReach, entries []inventory.Entry, policy policyOf) link.ChangePlan {
+	p := link.ChangePlan{Repository: repository, Base: base, Head: head, Moved: r.Moved(), Dependents: r.Dependents(),
+		New: r.Added, Unread: r.Unread, Tiers: r.Plan.Tiers}
+	byName := map[string]inventory.Entry{}
+	for _, e := range entries {
+		byName[e.Manifest.Module] = e
+	}
+	// The machine holding the bus, whose declaration carries every module's grants (novox/hq issue 490).
+	holder := ""
+	for _, e := range entries {
+		if e.Manifest.BusUsers != "" && e.Manifest.ClaimsSeat(catalogue.BrokerSeat) && len(e.On) > 0 {
+			holder = e.On[0]
+		}
+	}
+	var granting []string
+	machines := map[string]*link.MachinePlan{}
+	machine := func(name string) *link.MachinePlan {
+		if machines[name] == nil {
+			machines[name] = &link.MachinePlan{Machine: name}
+		}
+		return machines[name]
+	}
+	for _, tier := range r.Plan.Tiers {
+		for _, name := range tier {
+			e, held := byName[name]
+			if !held {
+				continue
+			}
+			u, known := policy(name)
+			waits := known && !u.RollOut
+			for _, on := range e.On {
+				if waits {
+					machine(on).Waits = append(machine(on).Waits, name)
+				} else {
+					machine(on).Receives = append(machine(on).Receives, name)
+				}
+			}
+			if !waits && holder != "" && !(len(e.On) == 1 && e.On[0] == holder) && len(e.On) > 0 &&
+				!slices.Contains(granting, name) {
+				granting = append(granting, name)
+			}
+			switch {
+			case (name == "nats" || catalogue.ProvidesBus(e.Manifest)) && len(e.On) > 0:
+				// Said before the merge (novox/hq issue 336): a new bus build holds every send to the bus's machine
+				// until a person takes the step, so merging it is a promise to take it.
+				p.Steps = append(p.Steps, fmt.Sprintf("%s: %s is never sent by an ordinary send, and until %s runs, "+
+					"nothing else is sent to %s either — unless the new build turns out the same as the one running there "+
+					"(issue 280)", busUpgradeNeeded, name, busUpgradeVerb, strings.Join(e.On, ", ")))
+			case name == "nats" || catalogue.ProvidesBus(e.Manifest):
+				p.Steps = append(p.Steps, "a planned bus step: the bus is upgraded by `bus upgrade`, never by an ordinary send")
+			case waits && len(e.On) > 0 && (u.From == catalogue.FromModule || u.From == catalogue.FromData):
+				// Judged per machine by the walk, against the build each was last sent (novox/hq ADR 0377).
+				p.Steps = append(p.Steps, fmt.Sprintf("%s waits for a person: its policy records (%s) — unless on a machine "+
+					"its move recreates none of its containers and moves none of its data, which the walk judges and then sends",
+					name, orNone(u.From)))
+			case waits && len(e.On) > 0:
+				p.Steps = append(p.Steps, fmt.Sprintf("%s waits for a person: its policy records (%s)", name,
+					orNone(u.From)))
+			}
+			if len(e.Manifest.Provides) > 0 && len(e.On) > 0 {
+				var offers []string
+				for _, o := range e.Manifest.Provides {
+					offers = append(offers, o.Name)
+				}
+				p.Steps = append(p.Steps, fmt.Sprintf("%s provides %s: its consumers are sent again after it",
+					name, strings.Join(offers, ", ")))
+			}
+			if e.Manifest.Data != nil && len(e.On) > 0 {
+				p.Steps = append(p.Steps, fmt.Sprintf("%s keeps data (ADR 0233): what it holds is backed up before it moves", name))
+			}
+		}
+	}
+	if len(granting) > 0 {
+		// Said before the merge (novox/hq issue 490): what the walk does when the change alters the bus's
+		// user list. Whether it does is known only once the builds are registered, so it is said as a rule.
+		p.Steps = append(p.Steps, fmt.Sprintf("%s: if this changes what the bus's user list says (a new tool, "+
+			"subject or user), %s is sent that list alone, every build there kept, before %s is judged on its first "+
+			"machine", grantsStepWord, holder, strings.Join(granting, ", ")))
+	}
+	var names []string
+	for name := range machines {
+		names = append(names, name)
+	}
+	sort.Strings(names)
+	for _, name := range names {
+		p.Machines = append(p.Machines, *machines[name])
+	}
+	p.Summary = summaryOf(p)
+	p.Class = changeClassOf(p, entries)
+	return p
+}
+
+// classNone is the class of a change that moves no module: nothing for a walk to move (novox/hq ADR 0313 §2).
+const classNone = "none"
+
+// changeClassOf is a change plan's class (novox/hq ADR 0313 §2): that of the slowest-budgeted module it moves,
+// itself or as a dependent — core when one is on the controller's own path or holds the mesh's resolver, leaf
+// otherwise — and none when it moves nothing. A module it adds a directory for counts by its own class: the
+// catalogue names a module's directory by the module, so the directory's last element is its name. The graph holds
+// no manifest of it yet, so a new module is core by its name alone (on the controller's own path), never by a
+// resolver claim its manifest makes.
+func changeClassOf(p link.ChangePlan, entries []inventory.Entry) string {
+	if len(p.Moved) == 0 && len(p.Dependents) == 0 && len(p.New) == 0 {
+		return classNone
+	}
+	modules := append(append([]string{}, p.Moved...), p.Dependents...)
+	for _, dir := range p.New {
+		if name := path.Base(strings.Trim(dir, "/")); name != "." && name != "/" && name != "" {
+			modules = append(modules, name)
+		}
+	}
+	return classOfModules(modules, entries)
+}
+
+// grantsStepWord names the grants step (novox/hq issue 490): the bus's user list sent alone to the machine
+// holding the bus ahead of a walk's gate. Not the bus step, which replaces the bus itself.
+const grantsStepWord = "grants step"
+
+// busUpgradeNeeded is how a change plan says that merging it holds the bus's machine for a person's step.
+const busUpgradeNeeded = "merging this needs a person's bus upgrade"
+
+// summaryOf is a change plan in one line: what it builds, where it goes, and whether the bus moves.
+func summaryOf(p link.ChangePlan) string {
+	if len(p.Moved) == 0 && len(p.New) == 0 {
+		return "builds nothing: the change touches no module of the mesh's graph"
+	}
+	var parts []string
+	what := strings.Join(p.Moved, ", ")
+	if len(p.Dependents) > 0 {
+		what += fmt.Sprintf(" (+%d dependent(s))", len(p.Dependents))
+	}
+	if len(p.New) > 0 {
+		if what != "" {
+			what += ", "
+		}
+		what += "new: " + strings.Join(p.New, ", ")
+	}
+	var to []string
+	for _, m := range p.Machines {
+		if len(m.Receives) > 0 {
+			to = append(to, m.Machine)
+		}
+	}
+	if len(to) > 0 {
+		parts = append(parts, "builds "+what+" → "+strings.Join(to, ", "))
+	} else {
+		parts = append(parts, "builds "+what+", sent nowhere")
+	}
+	bus := "no bus step"
+	for _, s := range p.Steps {
+		switch {
+		case strings.HasPrefix(s, busUpgradeNeeded):
+			bus = busUpgradeNeeded
+		case strings.HasPrefix(s, "a planned bus step") && bus == "no bus step":
+			bus = "a bus step"
+		}
+	}
+	parts = append(parts, bus)
+	waiting := 0
+	for _, m := range p.Machines {
+		waiting += len(m.Waits)
+	}
+	if waiting > 0 {
+		parts = append(parts, fmt.Sprintf("%d wait(s) for a person", waiting))
+	}
+	return strings.Join(parts, "; ")
+}
+
+// planText is a change plan as a person reads it, for the pull request's comment.
+func planText(p link.ChangePlan) string {
+	var b strings.Builder
+	fmt.Fprintf(&b, "change plan of %s at %.8s into %s: %s\n", p.Repository, p.Head, p.Base, p.Summary)
+	for i, tier := range p.Tiers {
+		fmt.Fprintf(&b, "  tier %d: %s\n", i, strings.Join(tier, ", "))
+	}
+	for _, m := range p.Machines {
+		line := "  " + m.Machine + ": "
+		if len(m.Receives) > 0 {
+			line += "receives " + strings.Join(m.Receives, ", ")
+		}
+		if len(m.Waits) > 0 {
+			if len(m.Receives) > 0 {
+				line += "; "
+			}
+			line += "waits for a person: " + strings.Join(m.Waits, ", ")
+		}
+		b.WriteString(line + "\n")
+	}
+	for _, s := range p.Steps {
+		b.WriteString("  - " + s + "\n")
+	}
+	if len(p.Unread) > 0 {
+		fmt.Fprintf(&b, "  read by no module's build: %s\n", strings.Join(p.Unread, ", "))
+	}
+	return b.String()
+}

cmd/mesh-controller/changeplan_test.go

@@ -0,0 +1,78 @@
+package main
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// **One commit, one change plan** (novox/hq ADR 0238): the planner's reach, laid out machine by machine in
+// the build plan's order, with what is not an ordinary send said — the bus step, a module that waits for a
+// person, a provider whose consumers follow it.
+func TestAChangePlanSaysWhatEachMachineReceives(t *testing.T) {
+	const catalogue_ = "http://forge.internal:20000/novox/mesh-catalog.git"
+	entry := func(name, path string, on ...string) inventory.Entry {
+		e := fromRepo(name, catalogue_, path)
+		e.Source.BuiltFrom = "old"
+		e.On = on
+		return e
+	}
+	nats := entry("nats", "modules/nats", "anchor")
+	nats.Manifest.Provides = []catalogue.Offer{{Name: "mesh-bus"}}
+	gitea := entry("gitea", "modules/gitea", "anchor")
+	held := entry("photos", "modules/photos", "anchor", "laptop")
+	tools := fromRepo("node-tools", "http://forge.internal:20000/novox/mesh-tools.git", "node-tools")
+	tools.On = []string{"anchor", "laptop"}
+	entries := []inventory.Entry{nats, gitea, held, tools}
+	edges := []inventory.Edge{{From: "node-tools", To: "nats", Kind: inventory.EdgeStandsOn}}
+	policy := func(module string) (inventory.Upgrade, bool) {
+		if module == "photos" {
+			return inventory.Upgrade{RollOut: false, From: "a person"}, true
+		}
+		return inventory.Upgrade{RollOut: true}, true
+	}
+	plan := func(paths ...string) link.ChangePlan {
+		m := link.SourceMoved{Owner: "novox", Repo: "mesh-catalog", Base: "main", Commit: "head", Paths: paths}
+		return changePlanOf("novox/mesh-catalog", "main", "head", reachOfMerge(m, entries, nil, edges), entries, policy)
+	}
+
+	p := plan("modules/gitea/index.ts")
+	if p.Summary != "builds gitea → anchor; no bus step" {
+		t.Errorf("one module's change reads %q", p.Summary)
+	}
+
+	p = plan("modules/nats/Dockerfile", "modules/photos/x.js")
+	if !strings.Contains(p.Summary, "needs a person's bus upgrade") || !strings.Contains(p.Summary, "2 wait(s) for a person") ||
+		!strings.Contains(p.Summary, "(+1 dependent(s))") {
+		t.Errorf("the bus and a held module read %q", p.Summary)
+	}
+	got := map[string]string{}
+	for _, m := range p.Machines {
+		got[m.Machine] = strings.Join(m.Receives, ",") + "|" + strings.Join(m.Waits, ",")
+	}
+	// The bus first, what stands on it after: the build plan's order, per machine.
+	if got["anchor"] != "nats,node-tools|photos" || got["laptop"] != "node-tools|photos" {
+		t.Errorf("the deploy plan reads %v", got)
+	}
+	text := strings.Join(p.Steps, "\n")
+	// Said before the merge (novox/hq issue 336): merging it holds every send to the bus's machine until a
+	// person runs the bus's step, and the verb that does.
+	for _, want := range []string{"merging this needs a person's bus upgrade", "nothing else is sent to anchor",
+		"mesh_call mesh-controller.bus", "the same as the one running there", "photos waits for a person",
+		"nats provides mesh-bus"} {
+		if !strings.Contains(text, want) {
+			t.Errorf("the steps do not say %q:\n%s", want, text)
+		}
+	}
+
+	p = plan("merge-check.sh")
+	if !strings.HasPrefix(p.Summary, "builds nothing") || len(p.Machines) != 0 || strings.Join(p.Unread, ",") != "merge-check.sh" {
+		t.Errorf("a root file's plan reads %+v", p)
+	}
+	if !strings.Contains(planText(p), "read by no module's build: merge-check.sh") {
+		t.Errorf("the plan's text does not say why nothing is built:\n%s", planText(p))
+	}
+}

cmd/mesh-controller/check.go

@@ -0,0 +1,337 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// moduleCheck judges manifests where they are written, with no mesh (novox/hq ADR 0037, issue 148).
+//
+// **The same functions registration runs, and nothing the command line adds** (ADR 0035): the strict
+// parse with every per-manifest problem, then the rules no single manifest can be judged against,
+// over exactly the manifests given. Somebody describing their own application in their own
+// repository runs this before pushing and finds out there, rather than when a running mesh refuses
+// the registration or, later, when a machine applies something that resolved and should not have.
+//
+// **What it cannot know without a store, it says.** The mesh's own seat set is the store's (ADR
+// 0122); this binary carries a compiled copy that the store overrides when loaded, so a claim on a
+// mesh seat is judged fully only at registration. A seat another module declares is unknown unless
+// that module's manifest is passed too. Both are printed as a note, not as a problem — a check that
+// refused what it could not see would teach people to ignore it.
+//
+// **And every identity against every bound it meets** (novox/hq ADR 0225, issue 263): each module's
+// identity, on a machine whose name is `longestMachine` characters, against the bound of every
+// provision it wants that a manifest given here offers. An overflow is refused in the pull request
+// that introduces it — a new requirement, a lowered bound, a longer slug — instead of on the
+// provider's machine when a real machine's name first meets the module's.
+// SomeManifestsVar, set by the merge gate, says the manifests given are only some of their repository's.
+const SomeManifestsVar = "MESH_MODULE_CHECK_SOME"
+
+func moduleCheck(paths []string, out io.Writer) error {
+	return moduleCheckFor(paths, catalogue.DefaultLongestMachine, out)
+}
+
+func moduleCheckFor(paths []string, longestMachine int, out io.Writer) error {
+	if len(paths) == 0 {
+		return errors.New("module check <manifest.json>... — one file per module; pass every " +
+			"manifest of a repository together so the rules between them are checked too")
+	}
+	shelf := catalogue.Shelf{}
+	faulted := map[string]bool{}
+	failed := 0
+	// The list of predefined keys at the root of the repository above each manifest (novox/hq ADR 0348 §7), read
+	// once per repository: a manifest naming a key is judged against the list its own tree holds.
+	lists := map[string]catalogue.PredefinedList{}
+	listOf := func(path string) (catalogue.PredefinedList, error) {
+		root := catalogue.RepositoryRoot(filepath.Dir(path))
+		if root == "" {
+			return nil, nil
+		}
+		if list, read := lists[root]; read {
+			return list, nil
+		}
+		list, err := catalogue.ReadPredefined(root)
+		if err != nil {
+			return nil, err
+		}
+		lists[root] = list
+		return list, nil
+	}
+	for _, path := range paths {
+		raw, err := os.ReadFile(path)
+		if err != nil {
+			fmt.Fprintf(out, "%s: %v\n", path, err)
+			failed++
+			continue
+		}
+		list, err := listOf(path)
+		if err != nil {
+			fmt.Fprintf(out, "%s: %v\n", path, err)
+			failed++
+			continue
+		}
+		m, err := catalogue.ParseManifestWith(raw, list)
+		if err == nil {
+			// Each template's text read from the tree beside the manifest, and judged as inline content is
+			// (novox/hq ADR 0349 §2): a missing template is refused by name.
+			m, err = catalogue.WithTemplatesFrom(m, filepath.Dir(path))
+		}
+		if err != nil {
+			fmt.Fprintf(out, "%s: %v\n", path, err)
+			failed++
+			continue
+		}
+		if first, twice := shelf[m.Module]; twice {
+			_ = first
+			fmt.Fprintf(out, "%s: %s was already given; two manifests name one module\n", path, m.Module)
+			failed++
+			continue
+		}
+		// A definition names no installation (novox/hq ADR 0112, ADR 0155): judged here, in the
+		// catalogue-wide test, and at registration, which refuses in the same words.
+		if wrong := catalogue.TrustProblems(m); len(wrong) > 0 {
+			for _, p := range wrong {
+				fmt.Fprintf(out, "%s: %s\n", path, p)
+			}
+			failed += len(wrong)
+			faulted[m.Module] = true
+		}
+		// A module that declares a setting names the keys of its mergeable files (novox/hq ADR 0326 §3,
+		// issue 574): judged where a definition is written, as at registration, never where a stored
+		// build is read again.
+		if wrong := catalogue.WrittenSettingsProblems(m); len(wrong) > 0 {
+			for _, p := range wrong {
+				fmt.Fprintf(out, "%s: %s\n", path, p)
+			}
+			failed += len(wrong)
+			faulted[m.Module] = true
+		}
+		// A module lives whole in one repository (novox/hq ADR 0420 §1, issue 1019): when the check is told the
+		// repository it runs for (MESH_CHECK_REPOSITORY, set by the build's check), an artifact building from
+		// another is refused, as the merge gate refuses it. A run by hand names no repository and judges none.
+		if repo := os.Getenv("MESH_CHECK_REPOSITORY"); repo != "" && m.Build != nil {
+			for _, a := range m.Build.Artifacts {
+				if a.Context != nil && a.Context.Repository != "" && !sameRepository(a.Context.Repository,
+					link.SourceMoved{Owner: ownerOf(repo), Repo: repoOf(repo)}) {
+					fmt.Fprintf(out, "%s: %s builds artifact %s from %s: a module lives whole in one repository "+
+						"(novox/hq ADR 0420 §1)\n", path, m.Module, a.Name, a.Context.Repository)
+					failed++
+					faulted[m.Module] = true
+				}
+			}
+		}
+		if named := catalogue.InstallationProblems(m); len(named) > 0 {
+			for _, p := range named {
+				fmt.Fprintf(out, "%s: %s\n", path, p)
+			}
+			failed += len(named)
+			faulted[m.Module] = true
+		}
+		shelf[m.Module] = m
+	}
+
+	// Between the manifests: a seat declared twice, a use of a seat nothing declares, a claim on
+	// a seat that does not exist. Run only over what parsed, because a problem inside one manifest
+	// has already been said and would be said again here in a worse form.
+	//
+	// **Over some of a repository's manifests, a seat none of them declares is a note** (novox/hq issue 364), as
+	// this command's own word says above: the merge gate passes only the manifests a change touches, and says so
+	// with SomeManifestsVar, so a module that uses or claims a seat another module declares (the operator
+	// channel's, a channel bench) was refused there for a manifest it was not given. Given every manifest — the
+	// catalogue's own check, and registration — it stays a refusal.
+	some := os.Getenv(SomeManifestsVar) != ""
+	problems := catalogue.CatalogueProblems(shelf)
+	sort.Strings(problems)
+	for _, p := range problems {
+		if some && catalogue.IsUndeclaredSeat(p) {
+			fmt.Fprintf(out, "note: %s among the manifests given; registration judges it against the whole catalogue, "+
+				"and passing the declaring module's manifest too judges it here\n", p)
+			continue
+		}
+		fmt.Fprintln(out, p)
+		failed++
+	}
+
+	// Between the manifests too: an identity against the bounds of the provisions it wants, which
+	// only the provider's manifest states.
+	identities := catalogue.IdentityProblems(shelf, longestMachine)
+	sort.Strings(identities)
+	for _, p := range identities {
+		fmt.Fprintln(out, p)
+	}
+	failed += len(identities)
+
+	// And the data each module keeps (novox/hq ADR 0233): a provider that grants says what it keeps for
+	// its consumers, a directory a container writes is declared, and no backup line is written by hand.
+	data := catalogue.DataProblems(shelf)
+	sort.Strings(data)
+	for _, p := range data {
+		fmt.Fprintln(out, p)
+	}
+	failed += len(data)
+
+	var names []string
+	for name := range shelf {
+		names = append(names, name)
+	}
+	sort.Strings(names)
+
+	// **Every long-running resource says how it is ready** (novox/hq ADR 0240 rule 8): warned until the
+	// date, refused from it. The count is the catalogue's: its merge check keeps the number and lets a
+	// change lower it, never raise it.
+	undeclared := 0
+	required := !checkNow().Before(catalogue.HealthRequiredFrom)
+	for _, name := range names {
+		missing := catalogue.Undeclared(shelf[name])
+		undeclared += len(missing)
+		if len(missing) == 0 {
+			continue
+		}
+		if required {
+			for _, id := range missing {
+				fmt.Fprintf(out, "%s: %s stays up and does not say how it is ready: a long-running resource declares "+
+					"health since %s (novox/hq ADR 0240 rule 8)\n", name, id, catalogue.HealthRequiredFrom.Format("2006-01-02"))
+			}
+			failed += len(missing)
+			faulted[name] = true
+		}
+	}
+
+	// **A file that asks for a setting and does not say whether it is trusted counts as trusted** (novox/hq issue
+	// 339): listed and counted, never refused, so an author can opt out a file nothing trusts.
+	unsaid := 0
+	for _, name := range names {
+		unsaid += len(catalogue.UnsaidTrust(shelf[name]))
+	}
+
+	for _, name := range names {
+		m := shelf[name]
+		if faulted[name] {
+			continue
+		}
+		fmt.Fprintf(out, "%s: ok", name)
+		if n := len(m.Tools); n > 0 {
+			fmt.Fprintf(out, ", %d tool(s)", n)
+		}
+		if len(m.Invokes) > 0 {
+			fmt.Fprintf(out, ", invokes %s", joinInvokes(m.Invokes))
+		}
+		// The state it keeps and reads (novox/hq ADR 0201), so a reviewer sees what lands on the bus.
+		if len(m.State) > 0 {
+			kept := make([]string, 0, len(m.State))
+			for _, s := range m.State {
+				kept = append(kept, s.Name)
+			}
+			fmt.Fprintf(out, ", keeps state %s", strings.Join(kept, ", "))
+		}
+		// And the logs it keeps, with their caps (novox/hq ADR 0297).
+		if len(m.Logs) > 0 {
+			kept := make([]string, 0, len(m.Logs))
+			for _, l := range m.Logs {
+				kept = append(kept, fmt.Sprintf("%s (%d MiB)", l.Name, l.Cap()))
+			}
+			fmt.Fprintf(out, ", keeps log %s", strings.Join(kept, ", "))
+		}
+		if len(m.Reads) > 0 {
+			fmt.Fprintf(out, ", reads %s", strings.Join(m.Reads, ", "))
+		}
+		// The data it keeps, by class, so a reviewer sees what the mesh will protect and how.
+		if items := m.DataItems(); len(items) > 0 {
+			kept := make([]string, 0, len(items))
+			for _, it := range items {
+				kept = append(kept, it.ID+" ("+it.Class+")")
+			}
+			fmt.Fprintf(out, ", keeps %s", strings.Join(kept, ", "))
+		}
+		// How what it runs is ready (ADR 0240): each declared check, and what is judged by liveness alone.
+		var checks []string
+		for _, r := range m.Resources {
+			if h, has, _ := catalogue.ReadHealth(r); has {
+				checks = append(checks, fmt.Sprintf("%v by %s", r["id"], catalogue.HealthWords(h)))
+			}
+		}
+		// And its own runtime's, where it runs as its own account (novox/hq ADR 0366).
+		if own, has := catalogue.OwnRuntimeHealth(m); has {
+			if h, _, _ := catalogue.ReadHealth(own); h.Kind != "" {
+				checks = append(checks, fmt.Sprintf("%v by %s", own["id"], catalogue.HealthWords(h)))
+			}
+		}
+		if len(checks) > 0 {
+			fmt.Fprintf(out, ", ready: %s", strings.Join(checks, "; "))
+		}
+		if missing := catalogue.UnsaidTrust(m); len(missing) > 0 {
+			fmt.Fprintf(out, "; WARNING: %s ask(s) for a setting and do(es) not say whether it is trusted, so it counts as "+
+				"trusted: set at the terminal alone; say %q false where nothing trusts it (novox/hq issue 339)",
+				strings.Join(missing, ", "), catalogue.TrustedField)
+		}
+		if missing := catalogue.Undeclared(m); len(missing) > 0 {
+			fmt.Fprintf(out, "; WARNING: %s stay(s) up and say(s) not how it is ready — judged by liveness alone, "+
+				"refused from %s (ADR 0240 rule 8)", strings.Join(missing, ", "), catalogue.HealthRequiredFrom.Format("2006-01-02"))
+		}
+		fmt.Fprintln(out)
+	}
+	// The count the catalogue keeps (ADR 0240 rule 8), in a line its merge check reads.
+	fmt.Fprintf(out, "%s %d\n", UndeclaredHealthLine, undeclared)
+	fmt.Fprintf(out, "%s %d\n", UnsaidTrustLine, unsaid)
+	if failed > 0 {
+		return fmt.Errorf("%d problem(s) in %d manifest(s)", failed, len(paths))
+	}
+	fmt.Fprintf(out, "%d manifest(s) checked. Judged against the seats this binary carries; a claim on "+
+		"one of the mesh's own seats is judged fully at registration, and a seat declared by a "+
+		"module not given here reads as unknown. Identities judged on a %d-character machine name, "+
+		"against the bounds of the providers given here\n", len(paths), longestMachine)
+	return nil
+}
+
+// UndeclaredHealthLine starts the line `module check` says the count of long-running resources without
+// `health` in, over the manifests given: the catalogue's merge check compares it with the number it keeps.
+const UndeclaredHealthLine = "long-running resources without health:"
+
+// UnsaidTrustLine starts the line `module check` says the count of files that ask for a setting and do not say
+// whether it is trusted, and so count as trusted (novox/hq issue 339).
+const UnsaidTrustLine = "files asking for a setting without saying whether it is trusted:"
+
+// checkNow is the clock `module check` judges the date by; a test sets it.
+var checkNow = time.Now
+
+func joinInvokes(invokes []string) string {
+	if len(invokes) == 1 && invokes[0] == "*" {
+		return "every tool"
+	}
+	s := ""
+	for i, t := range invokes {
+		if i > 0 {
+			s += ", "
+		}
+		s += t
+	}
+	return s
+}
+
+// manifestsUnder lists every module.json below a directory, for `module check <dir>`.
+func manifestsUnder(dir string) ([]string, error) {
+	var found []string
+	err := filepath.WalkDir(dir, func(path string, d os.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if d.IsDir() && (d.Name() == "node_modules" || d.Name() == ".git" || d.Name() == "dist") {
+			return filepath.SkipDir
+		}
+		if !d.IsDir() && d.Name() == "module.json" {
+			found = append(found, path)
+		}
+		return nil
+	})
+	sort.Strings(found)
+	return found, err
+}

cmd/mesh-controller/check_builds.go

@@ -0,0 +1,87 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"os"
+	"strconv"
+
+	"github.com/novox/mesh-controller/internal/builder"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// A pull request's check builds go when it closes (novox/hq ADR 0350 §5): the build seat keeps them in the artifact
+// store's scratch namespace for the walk of its merge to take. **Let go of where the moment is heard**: the
+// controller ends the walk answering a merge — after that walk took what it reuses — and the delivery's owner, which
+// hears the forge say a pull request closed unmerged, asks the `forget-checks` verb; both let go through the store,
+// as the controller's own collection does. The build seat's holders let go of anything a week old on their own,
+// so a word lost here leaves a week's builds, never more.
+
+// checkBuildsIn is the scratch namespace as the controller reaches the artifact store.
+func checkBuildsIn(ctx context.Context, inv *inventory.Inventory) (builder.Scratch, error) {
+	shelf, err := inv.Catalogue(ctx)
+	if err != nil {
+		return nil, err
+	}
+	address, err := artifactStoreAddress(ctx, inv, shelf, "")
+	if err != nil {
+		return nil, err
+	}
+	if address == "" {
+		return nil, errors.New("the artifact store is not on the mesh's network")
+	}
+	return builder.Registry{Address: address}, nil
+}
+
+// forgetChecks lets go of a pull request's check builds and answers what it did.
+var forgetChecks = func(ctx context.Context, inv *inventory.Inventory, pull builder.PullRef) (string, error) {
+	scratch, err := checkBuildsIn(ctx, inv)
+	if err != nil {
+		return "", err
+	}
+	n, err := scratch.Forget(ctx, pull)
+	if err != nil {
+		return "", fmt.Errorf("%s: %d check(s)' builds let go of, and not all: %w", pull, n, err)
+	}
+	return fmt.Sprintf("%s: %d check(s)' builds let go of", pull, n), nil
+}
+
+// forgetChecksOfWalk lets go, on the save that ends a walk, of the check builds of every pull request whose merge
+// it answers: the walk took what it reuses. Said, never fatal.
+func forgetChecksOfWalk(ctx context.Context, inv *inventory.Inventory, p inventory.Plan) {
+	if p.WalkSaid != inventory.WalkEnded || p.Delivery == nil {
+		return
+	}
+	for _, pull := range reuseAskOf(&p).Pulls {
+		said, err := forgetChecks(ctx, inv, builder.PullRef{Owner: pull.Owner, Repo: pull.Repo, Number: pull.Number})
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "%s: its check builds stay until the week's sweep: %v\n", p.ID, err)
+			continue
+		}
+		fmt.Printf("%s: %s\n", p.ID, said)
+	}
+}
+
+// forgetChecksCommand is `forget-checks <owner> <repo> <number>`: the verb the delivery's owner asks when the forge
+// says a pull request closed unmerged (novox/hq ADR 0350 §5).
+func forgetChecksCommand(ctx context.Context, args []string) error {
+	if len(args) != 3 {
+		return errors.New("forget-checks <owner> <repo> <number>")
+	}
+	number, err := strconv.Atoi(args[2])
+	if err != nil || number <= 0 {
+		return fmt.Errorf("%q is not a pull request's number", args[2])
+	}
+	open, err := openStores(ctx)
+	if err != nil {
+		return err
+	}
+	defer open.Close()
+	said, err := forgetChecks(ctx, open.inventory, builder.PullRef{Owner: args[0], Repo: args[1], Number: number})
+	if err != nil {
+		return err
+	}
+	fmt.Println(said)
+	return nil
+}

cmd/mesh-controller/check_builds_integration_test.go

@@ -0,0 +1,102 @@
+//go:build integration
+
+package main
+
+import (
+	"encoding/json"
+	"reflect"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+func TestOnlyAWalksAskTakesAChecksBuildAndADryRunNever(t *testing.T) {
+	p := &inventory.Plan{Delivery: &inventory.PlanDelivery{Merges: []inventory.PlanMerge{
+		{Repository: "novox/shop", Number: 7}, {Repository: "http://forge.invalid/novox/web.git", Number: 3},
+		{Repository: "novox/shop", Number: 7}, {Repository: "novox/shop"}}}}
+	asked := reuseAskOf(p)
+	if want := []link.PullRef{{Owner: "novox", Repo: "shop", Number: 7}, {Owner: "novox", Repo: "web", Number: 3}}; !reflect.DeepEqual(asked.Pulls, want) {
+		t.Fatalf("the walk names %+v", asked.Pulls)
+	}
+	walk := withReuse(t.Context(), asked)
+	if reuseAsked(walk, false) != asked {
+		t.Fatal("a walk's ask does not carry its leave")
+	}
+	if reuseAsked(walk, true) != nil {
+		t.Fatal("a dry run carries a leave to take a check's build")
+	}
+	if reuseAsked(t.Context(), false) != nil {
+		t.Fatal("an ask that is not a walk's carries a leave")
+	}
+}
+
+func TestAReusedCheckBuildIsRegisteredByItsDigestAndGatedAsABuiltOne(t *testing.T) {
+	withTheGate(t) // the first-machine gate's own path (novox/hq ADR 0360 keeps it for earlier walks)
+	g := aGateMesh(t)
+	ctx := t.Context()
+	inv := g.open.inventory
+	gateEvery = 0
+
+	digest := "sha256:" + strings.Repeat("c", 64)
+	reused := func(id, reference string) link.BuildResult {
+		manifest := mustJSON(t, catalogue.Manifest{Module: "app", Version: "c3", Resources: []map[string]any{
+			{"id": "svc", "type": "container", "name": "app", "image": reference}}})
+		return link.BuildResult{ID: id, Repository: "novox/mesh-catalog", Path: "modules/app", Ref: "main", On: "anchor",
+			Commit: "c3", Manifest: manifest, Trunk: "main", OnTrunk: true, Branches: []string{"main"},
+			Made:   []link.MadeArtifact{{Name: "server", Kind: "image", Reference: reference}},
+			Source: &link.SourceOnSeat{Seat: "git", Repository: "novox/mesh-catalog"},
+			Reused: "reused from the check of novox/mesh-catalog#9 at head abcdefabcdef (merged into trunk 123456123456): server " + digest,
+			ReusedFrom: &link.ReusedFrom{Pull: link.PullRef{Owner: "novox", Repo: "mesh-catalog", Number: 9},
+				Head: "abcdefabcdef", Trunk: "123456123456", Key: "r1:" + strings.Repeat("1", 64)}}
+	}
+	if _, _, err := takeIn(ctx, inv, reused(link.NewBuildID(time.Now()), "store.internal:5000/scratch/app/server@"+digest)); err == nil ||
+		!strings.Contains(err.Error(), "scratch") {
+		t.Fatalf("a build in the scratch namespace was registered: %v", err)
+	}
+	id := link.NewBuildID(time.Now().Add(time.Second))
+	result := reused(id, "store.internal:5000/app/server@"+digest)
+	if _, _, err := takeIn(ctx, inv, result); err != nil {
+		t.Fatal(err)
+	}
+	current, err := inv.CurrentBuilds(ctx)
+	if err != nil || current["app"].Commit != "c3" {
+		t.Fatalf("the reused build is not what app is registered at: %+v %v", current["app"], err)
+	}
+	shelf, err := inv.Catalogue(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+	raw, _ := json.Marshal(shelf["app"].Resources)
+	if !strings.Contains(string(raw), "app/server@"+digest) {
+		t.Fatalf("app is registered as %s, not by the check's digest in its own namespace", raw)
+	}
+
+	// The walk asked it: the walk keeps what its build did, and its gate judges the registered build.
+	asked := time.Now().UTC()
+	p := g.plan(t)
+	p.Commit = "c3"
+	p.Modules["app"] = &inventory.PlanModule{State: "asked", AskedAt: &asked, Build: id}
+	if err := inv.SavePlan(ctx, &p); err != nil {
+		t.Fatal(err)
+	}
+	planBuiltSaying(ctx, g.open, "app", "c3", "", asked, id, result.MadeWords())
+	p = g.plan(t)
+	if m := p.Modules["app"]; m.State != "built" || !strings.HasPrefix(m.Made, "reused from the check of novox/mesh-catalog#9") {
+		t.Fatalf("the walk keeps %+v", m)
+	}
+	for i := 0; i < 6; i++ {
+		advancePlans(ctx, g.open)
+	}
+	p = g.plan(t)
+	gate := p.Modules["app"].Gate
+	if gate == nil || gate.To != "c3" || gate.Verdict != inventory.GatePassed {
+		t.Fatalf("the gate judged %+v, not the reused build", gate)
+	}
+	if sent, _, _ := inv.SentBuilds(ctx, "anchor"); sent["app"] != "c3" {
+		t.Fatalf("the first machine was sent %v, not the reused build", sent)
+	}
+}

cmd/mesh-controller/check_builds_test.go

@@ -0,0 +1,193 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"reflect"
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/builder"
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// One build per change (novox/hq ADR 0350), as the controller asks it and takes it in.
+
+// The check of a change is asked to build what a merge of it would move, in the walk's order: a module of the
+// repository checked from the merge, one standing on it from its own repository as the walk builds it, and one
+// that reads the repository through a context not at all. A change that moves no module builds nothing.
+func TestACheckIsAskedToBuildWhatTheMergeWouldMove(t *testing.T) {
+	entries := []inventory.Entry{
+		{Manifest: catalogue.Manifest{Module: "app"}, Source: inventory.Source{Repository: "novox/shop", Seat: "git", Path: "modules/app"}},
+		{Manifest: catalogue.Manifest{Module: "web"}, Source: inventory.Source{Repository: "novox/web", Seat: "git", Ref: "main"}},
+		{Manifest: catalogue.Manifest{Module: "docs"}, Source: inventory.Source{Repository: "novox/docs", Seat: "git"}},
+	}
+	p := link.PullUpdated{Owner: "novox", Repo: "shop", Number: 7, Base: "main", Commit: "abc"}
+	scope := checkScope{Reach: mergeReach{Packaging: entries[2:], Plan: inventory.Plan{Tiers: [][]string{{"app", "docs"}, {"web"}}}}}
+	clone := func(s inventory.Source) (string, error) { return "http://forge.invalid/" + s.Repository + ".git", nil }
+
+	got := checkBuildsOf(p, scope, entries, clone)
+	want := []link.CheckBuild{
+		{Module: "app", Path: "modules/app", Merged: true, Tier: 0},
+		{Module: "docs", Tier: 0, Skip: "its build reads novox/shop through a context, which a check cannot hand the merge"},
+		{Module: "web", Repository: "http://forge.invalid/novox/web.git", Ref: "main", Tier: 1},
+	}
+	if !reflect.DeepEqual(got, want) {
+		t.Fatalf("the check is asked to build\n%+v\nwant\n%+v", got, want)
+	}
+	if got := checkBuildsOf(p, checkScope{}, entries, clone); got != nil {
+		t.Fatalf("a change that moves no module asks for builds: %+v", got)
+	}
+}
+
+// A walk's ask carries its leave to take a check's build, naming the pull requests of the merges it answers; a dry
+// run never does, and neither does an ask that is not a walk's.
+
+// A walk ended lets go of its merges' check builds — only once it ended, after it took what it reuses.
+func TestAWalkEndedLetsGoOfItsMergesCheckBuilds(t *testing.T) {
+	var forgot []builder.PullRef
+	was := forgetChecks
+	forgetChecks = func(_ context.Context, _ *inventory.Inventory, pull builder.PullRef) (string, error) {
+		forgot = append(forgot, pull)
+		return "", nil
+	}
+	t.Cleanup(func() { forgetChecks = was })
+	p := inventory.Plan{ID: "plan-1", Delivery: &inventory.PlanDelivery{Merges: []inventory.PlanMerge{
+		{Repository: "novox/shop", Number: 7}}}}
+
+	p.WalkSaid = inventory.WalkStarted
+	forgetChecksOfWalk(t.Context(), nil, p)
+	p.WalkSaid = ""
+	forgetChecksOfWalk(t.Context(), nil, p)
+	if len(forgot) != 0 {
+		t.Fatalf("a walk not ended let go of %v, which it may still take", forgot)
+	}
+	p.WalkSaid = inventory.WalkEnded
+	forgetChecksOfWalk(t.Context(), nil, p)
+	if want := []builder.PullRef{{Owner: "novox", Repo: "shop", Number: 7}}; !reflect.DeepEqual(forgot, want) {
+		t.Fatalf("the walk ended let go of %v", forgot)
+	}
+}
+
+// A build in the scratch namespace is never registered: only the walk's copy in the module's own namespace is.
+func TestABuildInTheScratchNamespaceIsNeverRegistered(t *testing.T) {
+	if got := inScratch([]link.MadeArtifact{{Name: "server", Reference: "store.internal:5000/app/server@sha256:aa"}}); got != "" {
+		t.Fatalf("a module's own build reads as a scratch build: %s", got)
+	}
+	scratch := "store.internal:5000/scratch/app/server@sha256:aa"
+	if got := inScratch([]link.MadeArtifact{{Name: "server", Reference: scratch}}); got != scratch {
+		t.Fatalf("a scratch build was not found: %q", got)
+	}
+	if got := inScratch([]link.MadeArtifact{{Name: "look", Reference: "http://store.internal:5000/v2/scratch/app/look/blobs/sha256:bb"}}); got == "" {
+		t.Fatal("a scratch archive was not found")
+	}
+}
+
+// The walk says per module what it did: "reused from …" or "built: <why>" — and a build seat from before says
+// neither, which is said.
+func TestAWalksBuildSaysWhetherItReusedOrBuilt(t *testing.T) {
+	if got := (link.BuildResult{Reused: "reused from the check of novox/shop#7"}).MadeWords(); got != "reused from the check of novox/shop#7" {
+		t.Fatalf("said %q", got)
+	}
+	if got := (link.BuildResult{BuiltWhy: "no check built it"}).MadeWords(); got != "built: no check built it" {
+		t.Fatalf("said %q", got)
+	}
+	if got := (link.BuildResult{}).MadeWords(); !strings.Contains(got, "predates ADR 0350") {
+		t.Fatalf("said %q", got)
+	}
+}
+
+// A walk's module the check's build stood in for is registered by the digest the check built — the copy in the
+// module's namespace — and the walk keeps "reused from …" for it; its first-node gate judges that registered
+// build as it judges one the walk built. A scratch reference is refused. Needs the store (MESH_TEST_POSTGRES), and
+// is named in testdata/store-tests.
+
+// A walk's leave names the builds its own pull requests' verdicts made at the head each merge merged — never an
+// earlier head's — read once per walk, and none when they cannot be read: the builder takes nothing a verdict does
+// not name (novox/hq ADR 0350 §2, issue 703).
+func TestAWalksLeaveNamesTheBuildsItsPullRequestsVerdictsMade(t *testing.T) {
+	was := checkedBuildsOf
+	forgetWalkVerdicts()
+	t.Cleanup(func() { checkedBuildsOf = was; forgetWalkVerdicts() })
+	var asked [][]link.PullRef
+	pull := link.PullRef{Owner: "novox", Repo: "shop", Number: 7}
+	atHead := link.CheckedBuild{Pull: pull, Check: "build-2", Head: "bbbbbbbbbbbb", Built: link.CheckBuilt{Module: "app", Key: "r1:2"}}
+	earlier := link.CheckedBuild{Pull: pull, Check: "build-1", Head: "aaaaaaaaaaaa", Built: link.CheckBuilt{Module: "app", Key: "r1:1"}}
+	checkedBuildsOf = func(_ context.Context, pulls []link.PullRef) ([]link.CheckedBuild, error) {
+		asked = append(asked, pulls)
+		return []link.CheckedBuild{atHead, earlier}, nil
+	}
+	pulls := []link.PullRef{pull}
+	heads := map[link.PullRef]string{pull: "bbbbbbbbbbbb0123456789"}
+	for range 3 {
+		if got := reuseWithVerdicts(t.Context(), "plan-1", &link.ReuseAsk{Pulls: pulls}, heads); !reflect.DeepEqual(got.Builds,
+			[]link.CheckedBuild{atHead}) {
+			t.Fatalf("the leave names %+v, not only the merged head's build", got.Builds)
+		}
+	}
+	if !reflect.DeepEqual(asked, [][]link.PullRef{pulls}) {
+		t.Fatalf("the verdicts were read %d times for one walk: %v", len(asked), asked)
+	}
+	// A merge whose head was not said takes nothing.
+	if got := reuseWithVerdicts(t.Context(), "plan-1", &link.ReuseAsk{Pulls: pulls}, nil); got.Builds != nil {
+		t.Fatalf("a merge of no said head names %+v", got.Builds)
+	}
+	checkedBuildsOf = func(context.Context, []link.PullRef) ([]link.CheckedBuild, error) {
+		return nil, errors.New("no bus")
+	}
+	if got := reuseWithVerdicts(t.Context(), "plan-2", &link.ReuseAsk{Pulls: pulls}, heads); got.Builds != nil {
+		t.Fatalf("verdicts that could not be read named %+v", got.Builds)
+	}
+}
+
+// A check is handed only the builds earlier checks of its own pull request at its own head made: another pull
+// request's build, or an earlier head's, is never kept (novox/hq issue 703). None when they cannot be read.
+func TestACheckIsHandedOnlyItsOwnHeadsBuilds(t *testing.T) {
+	was := checkedBuildsOf
+	t.Cleanup(func() { checkedBuildsOf = was })
+	pull := link.PullRef{Owner: "novox", Repo: "shop", Number: 7}
+	mine := link.CheckedBuild{Pull: pull, Check: "build-1", Head: "bbbbbbbbbbbb", Built: link.CheckBuilt{Module: "app", Key: "r1:1"}}
+	earlier := link.CheckedBuild{Pull: pull, Check: "build-0", Head: "aaaaaaaaaaaa", Built: link.CheckBuilt{Module: "app", Key: "r1:1"}}
+	another := link.CheckedBuild{Pull: link.PullRef{Owner: "novox", Repo: "shop", Number: 8}, Check: "build-9",
+		Head: "bbbbbbbbbbbb", Built: link.CheckBuilt{Module: "app", Key: "r1:1"}}
+	var asked [][]link.PullRef
+	checkedBuildsOf = func(_ context.Context, pulls []link.PullRef) ([]link.CheckedBuild, error) {
+		asked = append(asked, pulls)
+		return []link.CheckedBuild{mine, earlier, another}, nil
+	}
+	p := link.PullUpdated{Owner: "novox", Repo: "shop", Number: 7, Commit: "bbbbbbbbbbbb0123456789"}
+	builds := []link.CheckBuild{{Module: "app"}}
+	if got := namedForTheCheck(t.Context(), p, builds); !reflect.DeepEqual(got, []link.CheckedBuild{mine}) ||
+		!reflect.DeepEqual(asked, [][]link.PullRef{{pull}}) {
+		t.Fatalf("the check is handed %+v, read for %v", got, asked)
+	}
+	checkedBuildsOf = func(context.Context, []link.PullRef) ([]link.CheckedBuild, error) {
+		return nil, errors.New("no bus")
+	}
+	if got := namedForTheCheck(t.Context(), p, builds); got != nil {
+		t.Fatalf("verdicts that could not be read named %+v", got)
+	}
+}
+
+func forgetWalkVerdicts() {
+	walkVerdicts.Lock()
+	defer walkVerdicts.Unlock()
+	walkVerdicts.read = map[string]verdictsRead{}
+}
+
+// A walk's merged heads are the forge's word for each merge; a merge announced without its head, or a pull request
+// merged at two heads in one walk, has none, and its walk takes no check's build (novox/hq issue 703).
+func TestAWalksMergedHeadsAreTheForgesWord(t *testing.T) {
+	merge := func(number int, head string) inventory.PlanMerge {
+		return inventory.PlanMerge{Repository: "novox/shop", Number: number, Head: head}
+	}
+	p := &inventory.Plan{Delivery: &inventory.PlanDelivery{Merges: []inventory.PlanMerge{
+		merge(7, "aaaaaaaaaaaa1"), merge(8, ""), merge(9, "bbbbbbbbbbbb"), merge(9, "cccccccccccc")}}}
+	heads := mergedHeadsOf(p)
+	shop := func(n int) link.PullRef { return link.PullRef{Owner: "novox", Repo: "shop", Number: n} }
+	if heads[shop(7)] != "aaaaaaaaaaaa1" || heads[shop(8)] != "" || heads[shop(9)] != "" {
+		t.Fatalf("merged heads %v", heads)
+	}
+}

cmd/mesh-controller/check_here.go

@@ -0,0 +1,203 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"flag"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/builder"
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// `check-here` is a pull request's merge check run on the machine at hand **exactly as the build seat
+// runs it** (novox/hq issue 286): the same code (builder.Check), the same ask the controller would make of
+// the seat — the gate's modules and judge by the planner's own answer over the facts snapshot, the
+// repositories beside it at the refs the snapshot says the seat clones them at — in the toolchain image
+// the mesh holds, as the user the build seat runs as, against a throwaway store and bus of the versions
+// the mesh runs.
+//
+// **The build seat is the reference.** A merge-check.sh that passed on an agent's machine failed on the
+// seat for three reasons that were each the agent's environment, never the change: a newer Go whose gofmt
+// lays a file out differently, a sibling checkout at the agent's feature branch where the seat had the
+// commit the mesh runs, and a different user. Run here, a check sees what the seat will.
+//
+//	check-here [--tree <checkout>] [--base main] [--registry <artifact store>] [--forge <url of the owner>]
+//	           [--number <n>] [--user uid:gid] [--facts store|<file>] [--keep]
+//
+// The checkout's HEAD is what is checked, and it must be committed: the seat checks a commit, never a
+// working tree.
+func checkHereCommand(ctx context.Context, args []string) error {
+	set := flag.NewFlagSet("check-here", flag.ContinueOnError)
+	tree := set.String("tree", ".", "the change's checkout; its HEAD is checked")
+	base := set.String("base", "main", "the branch the change would merge into")
+	registry := set.String("registry", os.Getenv("MESH_REGISTRY"), "the artifact store holding the facts and the toolchains")
+	forge := set.String("forge", "", "where the repositories beside it are cloned from, as <forge>/<repository>.git; "+
+		"the checkout's origin without its own name when not given")
+	number := set.Int("number", 0, "the pull request's number, when there is one")
+	// The build seat's service runs as root, and its check containers run as the builder does.
+	user := set.String("user", "0:0", "the user the check's containers run as: the build seat's")
+	keep := set.Bool("keep", false, "keep the workspace afterwards")
+	factsFrom := set.String("facts", "store", "the facts snapshot: `store`, the one the artifact store holds — "+
+		"what the seat reads — or a file")
+	if _, err := parseAround(set, args); err != nil {
+		return err
+	}
+	if *registry == "" {
+		return errors.New("check-here reads the facts and the toolchains from the artifact store: --registry <host:port> or MESH_REGISTRY")
+	}
+	dir, err := filepath.Abs(*tree)
+	if err != nil {
+		return err
+	}
+	git := func(args ...string) (string, error) {
+		cmd := exec.CommandContext(ctx, "git", args...)
+		cmd.Dir = dir
+		out, err := cmd.Output()
+		return strings.TrimSpace(string(out)), err
+	}
+	if dirty, err := git("status", "--porcelain", "--untracked-files=no"); err != nil {
+		return fmt.Errorf("%s is not a checkout: %w", dir, err)
+	} else if dirty != "" {
+		return errors.New("the checkout has changes not committed: the build seat checks a commit, so commit first")
+	}
+	head, err := git("rev-parse", "HEAD")
+	if err != nil {
+		return err
+	}
+	origin, err := git("remote", "get-url", "origin")
+	if err != nil {
+		return fmt.Errorf("the checkout has no origin to say which repository it is: %w", err)
+	}
+	owner, repo, prefix := ownerRepoOf(origin)
+	if *forge == "" {
+		*forge = prefix
+	}
+	if _, err := git("fetch", "--quiet", "origin", *base); err != nil {
+		return fmt.Errorf("cannot fetch %s to say what the change touches: %w", *base, err)
+	}
+	// Without rename detection, so a file moved out of a build source is said under its old name as well:
+	// its going is a change to the build that held it (novox/hq ADR 0267).
+	changedText, err := git("diff", "--name-only", "--no-renames", "origin/"+*base+"...HEAD")
+	if err != nil {
+		return err
+	}
+	var paths, removed []string
+	for _, p := range strings.Split(changedText, "\n") {
+		if p = strings.TrimSpace(p); p == "" {
+			continue
+		}
+		paths = append(paths, p)
+		if _, err := os.Stat(filepath.Join(dir, p)); os.IsNotExist(err) {
+			removed = append(removed, p)
+		}
+	}
+
+	_ = os.Setenv("MESH_REGISTRY", *registry)
+	f, err := readFacts(ctx, *factsFrom)
+	if err != nil {
+		return fmt.Errorf("the facts snapshot cannot be read: %w", err)
+	}
+	entries, read, edges, err := graphOfFacts(f)
+	if err != nil {
+		return err
+	}
+	p := link.PullUpdated{Owner: owner, Repo: repo, Number: *number, Base: *base, Commit: head, Paths: paths,
+		Removed: removed, ModuleDirs: moduleDirsIn(dir, paths), ModuleDirsSaid: true}
+	scope := pullScope(p, entries, read, edges)
+	_, scriptErr := os.Stat(filepath.Join(dir, builder.CheckScript))
+	if !scope.gated() && !scope.Mesh {
+		fmt.Printf("%s: %s, and the repository is not the mesh's: the build seat runs nothing for it\n",
+			owner+"/"+repo, noModuleTouched)
+		return nil
+	}
+	if !scope.gated() && scriptErr != nil {
+		fmt.Printf("%s: %s; %s\n", owner+"/"+repo, noModuleTouched, noMergeCheck)
+		return nil
+	}
+
+	toolchains := map[string]string{}
+	for language, reference := range f.Versions.Toolchains {
+		toolchains[language] = catalogue.Rerouted(reference, *registry)
+	}
+	if len(toolchains) == 0 {
+		return errors.New("the facts snapshot names no toolchain: it was taken by a controller from before " +
+			"issue 286, and the seat's toolchain cannot be known here")
+	}
+	beside := map[string]builder.Beside{}
+	for d, ref := range f.Beside {
+		from := d
+		if d == "mesh-controller-main" {
+			from = "mesh-controller"
+		}
+		beside[d] = builder.Beside{Repository: strings.TrimSuffix(*forge, "/") + "/" + from + ".git", Ref: ref}
+	}
+	id := fmt.Sprintf("check-here-%d", time.Now().UnixNano())
+	spec := builder.CheckSpec{ID: id, Repository: dir, Ref: head, Owner: owner, Repo: repo, Number: *number,
+		Paths: paths, Beside: beside, Modules: scope.Modules, New: scope.New, Manifests: scope.Manifests,
+		Base: *base, Judge: scope.Judge, Toolchain: toolchains["go"], Toolchains: toolchains, User: *user}
+
+	workspace, err := os.MkdirTemp("", "mesh-check-here-")
+	if err != nil {
+		return err
+	}
+	if !*keep {
+		defer removeWorkspace(spec.Toolchain, workspace, *user)
+	}
+	fmt.Fprintf(os.Stderr, "checking %s/%s at %.8s as the build seat would, against the facts of %s, in %s\n",
+		owner, repo, head, f.Taken.Format(time.RFC3339), workspace)
+	v, err := builder.Check(ctx, builder.Command, spec, workspace, *registry, builder.GitCredential{},
+		func(step, message string) {
+			if step != "output" {
+				fmt.Fprintf(os.Stderr, "  [%s] %s\n", step, message)
+			}
+		})
+	if err != nil {
+		return fmt.Errorf("the check could not run — on the seat an error, never a pass: %w", err)
+	}
+	fmt.Println(v.Report)
+	fmt.Println()
+	fmt.Printf("mesh/merge-gate: %s — %s\n", strings.ToUpper(v.Gate.Verdict), v.Gate.Summary)
+	if v.Repo != nil {
+		fmt.Printf("mesh/repo-check: %s — %s\n", strings.ToUpper(v.Repo.Verdict), v.Repo.Summary)
+	}
+	for _, l := range []*builder.Layer{v.Gate, v.Repo} {
+		if l != nil && l.Verdict != "pass" && l.Verdict != "warning" {
+			return errors.New("the build seat would not pass this change")
+		}
+	}
+	return nil
+}
+
+// ownerRepoOf reads owner, repository and the owner's URL from a remote: ssh://git@host:222/novox/mesh-host.git
+// → novox, mesh-host, ssh://git@host:222/novox.
+func ownerRepoOf(remote string) (string, string, string) {
+	trimmed := strings.TrimSuffix(strings.TrimSuffix(remote, "/"), ".git")
+	cut := strings.LastIndexAny(trimmed, "/:")
+	if cut < 0 {
+		return "", trimmed, ""
+	}
+	repo, prefix := trimmed[cut+1:], trimmed[:cut]
+	owner := prefix
+	if at := strings.LastIndexAny(prefix, "/:"); at >= 0 {
+		owner = prefix[at+1:]
+	}
+	return owner, repo, prefix
+}
+
+// removeWorkspace removes what the check left, written as the seat's user: by a container of that user
+// when it is not this one.
+func removeWorkspace(image, workspace, user string) {
+	if image != "" && user != fmt.Sprintf("%d:%d", os.Getuid(), os.Getgid()) {
+		// Everything in it — the check's HOME is the workspace, so the toolchain's own files are there too.
+		_ = exec.Command("docker", "run", "--rm", "--user", user, "--volume", workspace+":/workspace", image,
+			"sh", "-c", "rm -rf /workspace/* /workspace/.[!.]*").Run()
+	}
+	_ = os.RemoveAll(workspace)
+}

cmd/mesh-controller/check_siblings.go

@@ -0,0 +1,165 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"regexp"
+	"sort"
+	"strings"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// **A delivery group's member is checked beside the other members' heads** (novox/hq ADR 0382, issue 867).
+//
+// A mesh-host change and a mesh-controller change that need each other could not both pass their own merge checks:
+// each was read beside the other's repository at the commit the mesh runs, which holds neither change. So the
+// controller asks mesh-delivery's `groups` once for every pull request's check it asks (§1), and names, in the ask,
+// the group's other open pull requests into a base of the same name, in a repository the build seat reads beside the
+// check — mesh-lab never — each with its whole head. The build seat reads those repositories at the sibling's merge (§2).
+// A pull request for which mesh-delivery answered and named no sibling is asked exactly as before (§7).
+
+// wholeCommit is a commit as the forge says a head: forty hexadecimal characters.
+var wholeCommit = regexp.MustCompile(`^[0-9a-f]{40}$`)
+
+// besideRepositories are the repositories (lower case, owner/repo) a check reads beside its own, by the directory each
+// is found under — the core's, as besideOf clones them, and mesh-sdk beside the controller; never mesh-lab, which is
+// always read at its trunk.
+func besideRepositories(entries []inventory.Entry) map[string]string {
+	read := map[string]string{}
+	for _, e := range entries {
+		dir, core := coreModules[e.Manifest.Module]
+		if !core || e.Provided || e.Source.Repository == "" {
+			continue
+		}
+		read[nameOf(e.Source.Repository)] = dir
+		if dir == "mesh-controller" && e.Source.Seat != "" {
+			read[nameOf(siblingOf(e.Source.Repository, "mesh-sdk"))] = "mesh-sdk"
+		}
+	}
+	delete(read, "")
+	return read
+}
+
+// nameOf is a recorded repository as owner/repo in lower case, empty when it names no owner.
+func nameOf(repository string) string {
+	owner, repo := sourceOwner(repository), sourceName(repository)
+	if owner == "" || repo == "" {
+		return ""
+	}
+	return strings.ToLower(owner + "/" + repo)
+}
+
+// siblingsFor is the pull request's siblings, as mesh-delivery's groups say them (ADR 0382 §1): the other members of
+// the group its head branch names that are open, unmerged and into a base of its own base's name, in a repository the
+// check reads beside it (beside: the directories the ask already names). The second answer is why they could not be
+// learned, empty when they could: the group's members carry no head or base — a mesh-delivery from before the rule.
+func siblingsFor(p link.PullUpdated, entries []inventory.Entry, beside map[string]link.CheckedOut,
+	lines []groupsLine) ([]link.CheckSibling, string) {
+	own := strings.ToLower(p.Owner + "/" + p.Repo)
+	var group *groupsLine
+	if p.Head == "" {
+		// A recheck (mesh-delivery's `recheck` through `delivery check`) carries no head branch name: the group is the one
+		// whose members hold this very pull request, by repository and number.
+		learnable := false
+		for i := range lines {
+			for _, m := range lines[i].Details {
+				learnable = true
+				if p.Number != 0 && m.Number == p.Number && strings.ToLower(m.Repository) == own {
+					group = &lines[i]
+				}
+			}
+		}
+		if group == nil {
+			for _, l := range lines {
+				if len(l.Details) == 0 && len(l.Members) > 0 && !learnable {
+					return nil, "mesh-delivery named the groups' members without their pull requests (a mesh-delivery from before novox/hq ADR 0382): " +
+						"the group of a pull request announced without its head branch cannot be found"
+				}
+			}
+			return nil, "" // a lone pull request
+		}
+	} else {
+		for i := range lines {
+			if lines[i].ID == p.Head {
+				group = &lines[i]
+			}
+		}
+		if group == nil {
+			return nil, ""
+		}
+	}
+	if len(group.Details) == 0 && len(group.Members) > 0 {
+		return nil, "mesh-delivery named the group's members without their heads and bases (a mesh-delivery from before novox/hq ADR 0382)"
+	}
+	read := besideRepositories(entries)
+	var siblings []link.CheckSibling
+	for _, m := range group.Details {
+		repository := strings.ToLower(m.Repository)
+		if repository == own {
+			continue
+		}
+		if !m.Open {
+			continue
+		}
+		if m.Head == "" || m.Base == "" {
+			return nil, "mesh-delivery named " + m.ID + " without its head or base (a mesh-delivery from before novox/hq ADR 0382)"
+		}
+		dir, readBeside := read[repository]
+		if m.Base != p.Base || !readBeside || dir == "mesh-lab" {
+			continue
+		}
+		if _, there := beside[dir]; !there {
+			continue
+		}
+		head := strings.ToLower(m.Head)
+		if !wholeCommit.MatchString(head) {
+			return nil, fmt.Sprintf("mesh-delivery named %s with a head that is not a whole commit (%q)", m.ID, m.Head)
+		}
+		siblings = append(siblings, link.CheckSibling{Repository: m.Repository, Number: m.Number, Head: head, Base: m.Base, Dir: dir})
+	}
+	sort.Slice(siblings, func(i, j int) bool { return siblings[i].Dir < siblings[j].Dir })
+	return siblings, ""
+}
+
+// withSiblings asks mesh-delivery's `groups` once and says in the request the pull request's siblings, or why they
+// could not be learned (ADR 0382 §1): a check never waits on mesh-delivery past groupAskWithin and never fails for it,
+// so a fix to mesh-delivery is still checked without it.
+func withSiblings(ctx context.Context, request *link.BuildRequest, p link.PullUpdated, entries []inventory.Entry) {
+	lines, err := groupsAsked(ctx, deliverySeatHeld(entries))
+	siblingsFrom(request, p, entries, lines, err)
+}
+
+// siblingsFrom is withSiblings from mesh-delivery's answer already had.
+func siblingsFrom(request *link.BuildRequest, p link.PullUpdated, entries []inventory.Entry, lines []groupsLine, err error) {
+	if request.Check == nil {
+		return
+	}
+	if err != nil {
+		request.Check.SiblingsUnknown = fmt.Sprintf("mesh-delivery did not say the group's pull requests (%v): "+
+			"the check reads no siblings", err)
+		return
+	}
+	request.Check.Siblings, request.Check.SiblingsUnknown = siblingsFor(p, entries, request.Check.Beside, lines)
+}
+
+// composedMember says the pull request is a member of a delivery group whose gate is the composed check's (novox/hq
+// ADR 0403 clauses 1 and 7): the group has two members or more and mesh-delivery says so on its line. The group is
+// found as siblingsFor finds it, by its head branch name, or, for a recheck that carries none, by the pull request's
+// repository and number — not by siblings, which name only what the check reads beside it.
+func composedMember(p link.PullUpdated, lines []groupsLine) bool {
+	own := strings.ToLower(p.Owner + "/" + p.Repo)
+	for _, l := range lines {
+		found := p.Head != "" && l.ID == p.Head
+		for _, m := range l.Details {
+			if p.Head == "" && p.Number != 0 && m.Number == p.Number && strings.ToLower(m.Repository) == own {
+				found = true
+			}
+		}
+		if found {
+			return l.ComposedGate && max(len(l.Details), len(l.Members)) >= 2
+		}
+	}
+	return false
+}

cmd/mesh-controller/check_siblings_test.go

@@ -0,0 +1,248 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// **A delivery group's member is checked beside the other members' heads** (novox/hq ADR 0382 §1, §7, issue 867): the
+// controller asks mesh-delivery's `groups` once for every check it asks, and names in the ask the group's other open
+// pull requests into a base of the same name, in a repository the build seat reads beside it — mesh-lab never.
+
+const (
+	headHost       = "1111111111111111111111111111111111111111"
+	headController = "2222222222222222222222222222222222222222"
+	headSDK        = "3333333333333333333333333333333333333333"
+	headLab        = "4444444444444444444444444444444444444444"
+	headHq         = "5555555555555555555555555555555555555555"
+)
+
+func theCoreOnTheGitSeat() []inventory.Entry {
+	onSeat := func(module, repository string) inventory.Entry {
+		e := fromRepo(module, repository, "")
+		e.Source.Seat = "git"
+		return e
+	}
+	nats := onSeat("nats", "novox/mesh-catalog")
+	nats.Source.Path = "modules/nats"
+	held := catalogue.Manifest{Module: "mesh-delivery", Claims: []catalogue.Claim{{Name: catalogue.DeliverySeat, Scope: catalogue.ScopeMesh}}}
+	return []inventory.Entry{onSeat("mesh-controller", "novox/mesh-controller"), onSeat("mesh-host", "novox/mesh-host"),
+		onSeat("node-tools", "novox/mesh-tools"), nats, {Manifest: held, On: []string{"anchor"}}}
+}
+
+func besideTheCore() map[string]link.CheckedOut {
+	return map[string]link.CheckedOut{"mesh-controller": {Repository: "c"}, "mesh-host": {Repository: "h"},
+		"mesh-tools": {Repository: "t"}, "mesh-catalog": {Repository: "k"}, "mesh-sdk": {Repository: "s"}, "mesh-lab": {Repository: "l"}}
+}
+
+func member(repository string, number int, head, base string, open bool) memberLine {
+	return memberLine{ID: repository + "@" + head[:12], Repository: repository, State: "checked", Number: number, Head: head,
+		Base: base, Open: open}
+}
+
+func group(id string, members ...memberLine) groupsLine {
+	line := groupsLine{ID: id, Details: members}
+	for _, m := range members {
+		line.Members = append(line.Members, m.ID+" ("+m.State+")")
+	}
+	return line
+}
+
+func TestASiblingIsTheGroupsOtherOpenPullRequestIntoABaseOfTheSameName(t *testing.T) {
+	entries := theCoreOnTheGitSeat()
+	pull := link.PullUpdated{Owner: "novox", Repo: "mesh-host", Number: 114, Base: "main", Head: "feat/x", Commit: headHost}
+	for _, c := range []struct {
+		what    string
+		lines   []groupsLine
+		want    []string
+		unknown string
+	}{
+		{"the other member, open, same base", []groupsLine{group("feat/x",
+			member("novox/mesh-host", 114, headHost, "main", true), member("novox/mesh-controller", 346, headController, "main", true))},
+			[]string{"mesh-controller=novox/mesh-controller#346@" + headController + " onto main"}, ""},
+		{"a member into a base of another name is not one", []groupsLine{group("feat/x",
+			member("novox/mesh-host", 114, headHost, "main", true), member("novox/mesh-controller", 346, headController, "release", true))},
+			nil, ""},
+		{"a member not open (merged or closed) is not one", []groupsLine{group("feat/x",
+			member("novox/mesh-host", 114, headHost, "main", true), member("novox/mesh-controller", 346, headController, "main", false))},
+			nil, ""},
+		{"mesh-lab is never one", []groupsLine{group("feat/x",
+			member("novox/mesh-host", 114, headHost, "main", true), member("novox/mesh-lab", 5, headLab, "main", true))},
+			nil, ""},
+		{"a repository the check reads nothing of is not one", []groupsLine{group("feat/x",
+			member("novox/mesh-host", 114, headHost, "main", true), member("novox/hq", 9, headHq, "main", true))},
+			nil, ""},
+		{"mesh-sdk, read beside the controller, is one", []groupsLine{group("feat/x",
+			member("novox/mesh-host", 114, headHost, "main", true), member("novox/mesh-sdk", 7, headSDK, "main", true))},
+			[]string{"mesh-sdk=novox/mesh-sdk#7@" + headSDK + " onto main"}, ""},
+		{"another group is none of its business", []groupsLine{group("feat/y",
+			member("novox/mesh-host", 114, headHost, "main", true), member("novox/mesh-controller", 346, headController, "main", true))},
+			nil, ""},
+		{"a group of its own alone has none", []groupsLine{group("feat/x", member("novox/mesh-host", 114, headHost, "main", true))},
+			nil, ""},
+		{"an older mesh-delivery names no heads", []groupsLine{{ID: "feat/x",
+			Members: []string{"novox/mesh-host@111111111111 (checked)", "novox/mesh-controller@222222222222 (checked)"}}},
+			nil, "without their heads and bases"},
+		{"a member without its base", []groupsLine{group("feat/x",
+			member("novox/mesh-host", 114, headHost, "main", true), member("novox/mesh-controller", 346, headController, "", true))},
+			nil, "without its head or base"},
+		{"a head that is no commit", []groupsLine{group("feat/x",
+			member("novox/mesh-host", 114, headHost, "main", true), member("novox/mesh-controller", 346, headController[:12]+"zzzzzzzzzzzzzzzzzzzzzzzzzzzz", "main", true))},
+			nil, "not a whole commit"},
+	} {
+		got, unknown := siblingsFor(pull, entries, besideTheCore(), c.lines)
+		var said []string
+		for _, s := range got {
+			said = append(said, s.Dir+"="+s.Repository+"#"+itoa(s.Number)+"@"+s.Head+" onto "+s.Base)
+		}
+		if strings.Join(said, ";") != strings.Join(c.want, ";") {
+			t.Errorf("%s: siblings %v, wanted %v", c.what, said, c.want)
+		}
+		if (c.unknown == "") != (unknown == "") || !strings.Contains(unknown, c.unknown) {
+			t.Errorf("%s: could not learn %q, wanted %q", c.what, unknown, c.unknown)
+		}
+	}
+	// A pull request into a release branch has siblings into the release branch of the same name (ADR 0358 §1).
+	release := pull
+	release.Base = "feat/57"
+	lines := []groupsLine{group("feat/x", member("novox/mesh-host", 114, headHost, "feat/57", true),
+		member("novox/mesh-controller", 346, headController, "feat/57", true), member("novox/mesh-tools", 8, headLab, "main", true))}
+	if got, _ := siblingsFor(release, entries, besideTheCore(), lines); len(got) != 1 || got[0].Dir != "mesh-controller" {
+		t.Errorf("into a release branch: %+v", got)
+	}
+	// A recheck announces the pull request without its head branch: its group is the one holding it (repository, number).
+	pull.Head = ""
+	got, unknown := siblingsFor(pull, entries, besideTheCore(), lines)
+	if len(got) != 1 || got[0].Dir != "mesh-tools" || unknown != "" {
+		t.Errorf("a recheck of a group member: %+v %q", got, unknown)
+	}
+	// A pull request in no group, rechecked, is alone: no sibling, and nothing said.
+	pull.Number = 999
+	if got, unknown := siblingsFor(pull, entries, besideTheCore(), lines); got != nil || unknown != "" {
+		t.Errorf("a lone pull request: %+v %q", got, unknown)
+	}
+	if got, unknown := siblingsFor(pull, entries, besideTheCore(), nil); got != nil || unknown != "" {
+		t.Errorf("no groups at all: %+v %q", got, unknown)
+	}
+	// A mesh-delivery that names members without their pull requests cannot find the group of a recheck: it says so.
+	older := []groupsLine{{ID: "feat/x", Members: []string{"novox/mesh-host@111111111111 (checked)"}}}
+	pull.Number = 114
+	if got, unknown := siblingsFor(pull, entries, besideTheCore(), older); got != nil || unknown == "" {
+		t.Errorf("an older mesh-delivery: %+v %q", got, unknown)
+	}
+}
+
+func itoa(n int) string { b, _ := json.Marshal(n); return string(b) }
+
+// Every check asks mesh-delivery's `groups` once; the ask names the sibling's repository, head and base.
+func TestEveryCheckAsksMeshDeliveryOnceAndNamesItsSiblings(t *testing.T) {
+	entries := theCoreOnTheGitSeat()
+	asked := 0
+	was := groupsAsked
+	t.Cleanup(func() { groupsAsked = was })
+	groupsAsked = func(_ context.Context, held bool) ([]groupsLine, error) {
+		asked++
+		if !held {
+			t.Error("the seat is held, yet it was asked as not held")
+		}
+		return []groupsLine{group("feat/x", member("novox/mesh-host", 114, headHost, "main", true),
+			member("novox/mesh-controller", 346, headController, "main", true))}, nil
+	}
+	request := link.BuildRequest{Check: &link.CheckRequest{Owner: "novox", Repo: "mesh-host", Base: "main", Beside: besideTheCore()}}
+	withSiblings(t.Context(), &request, link.PullUpdated{Owner: "novox", Repo: "mesh-host", Base: "main", Head: "feat/x"}, entries)
+	if asked != 1 {
+		t.Fatalf("mesh-delivery was asked %d times for one check", asked)
+	}
+	want := link.CheckSibling{Repository: "novox/mesh-controller", Number: 346, Head: headController, Base: "main", Dir: "mesh-controller"}
+	if got := request.Check.Siblings; len(got) != 1 || got[0] != want || request.Check.SiblingsUnknown != "" {
+		t.Fatalf("the ask names siblings %+v, unknown %q", got, request.Check.SiblingsUnknown)
+	}
+	body, _ := json.Marshal(request.Check)
+	if !strings.Contains(string(body), `"siblings":[{"repository":"novox/mesh-controller","number":346,"head":"`+headController+
+		`","base":"main","dir":"mesh-controller"}]`) {
+		t.Fatalf("on the wire: %s", body)
+	}
+}
+
+// When mesh-delivery does not answer in time (or is not held, or answered without the fields), the check reads no
+// sibling and its request says it could not learn them, so a fix to mesh-delivery is still checked without it.
+func TestWhenMeshDeliveryDoesNotAnswerTheCheckReadsNoSiblingAndSaysSo(t *testing.T) {
+	was := groupsAsked
+	t.Cleanup(func() { groupsAsked = was })
+	for _, c := range []struct {
+		what string
+		err  error
+		held bool
+	}{{"it did not answer", context.DeadlineExceeded, true}, {"nothing serves it", errors.New("nothing serves mesh-delivery.groups"), true},
+		{"no holder on record", errors.New("no holder of mesh-delivery is on record to say it"), false}} {
+		entries := theCoreOnTheGitSeat()
+		if !c.held {
+			entries = entries[:4]
+		}
+		groupsAsked = func(_ context.Context, held bool) ([]groupsLine, error) {
+			if held != c.held {
+				t.Errorf("%s: held %v", c.what, held)
+			}
+			return nil, c.err
+		}
+		request := link.BuildRequest{Check: &link.CheckRequest{Owner: "novox", Repo: "mesh-host", Base: "main", Beside: besideTheCore()}}
+		withSiblings(t.Context(), &request, link.PullUpdated{Owner: "novox", Repo: "mesh-host", Base: "main", Head: "feat/x"}, entries)
+		if len(request.Check.Siblings) != 0 || !strings.Contains(request.Check.SiblingsUnknown, c.err.Error()) ||
+			!strings.Contains(request.Check.SiblingsUnknown, "reads no siblings") {
+			t.Errorf("%s: siblings %+v, unknown %q", c.what, request.Check.Siblings, request.Check.SiblingsUnknown)
+		}
+	}
+}
+
+// **A pull request for which mesh-delivery answered and named no sibling is asked exactly as before** (ADR 0382 §7):
+// byte for byte the request it was without the rule.
+func TestAPullRequestWithNoSiblingIsAskedByteForByteAsBefore(t *testing.T) {
+	entries := theCoreOnTheGitSeat()
+	was := groupsAsked
+	t.Cleanup(func() { groupsAsked = was })
+	for _, answer := range [][]groupsLine{nil, {group("feat/other", member("novox/mesh-controller", 346, headController, "main", true))},
+		{group("feat/x", member("novox/mesh-host", 114, headHost, "main", true), member("novox/hq", 3, headHq, "main", true))}} {
+		groupsAsked = func(context.Context, bool) ([]groupsLine, error) { return answer, nil }
+		build := func() link.BuildRequest {
+			return link.BuildRequest{ID: "build-1", Repository: "r", Ref: headHost, Check: &link.CheckRequest{Owner: "novox",
+				Repo: "mesh-host", Number: 114, Base: "main", Beside: besideTheCore(), Modules: []string{"mesh-host"}, Judge: "validator"}}
+		}
+		before, _ := json.Marshal(build())
+		after := build()
+		withSiblings(t.Context(), &after, link.PullUpdated{Owner: "novox", Repo: "mesh-host", Base: "main", Head: "feat/x"}, entries)
+		got, _ := json.Marshal(after)
+		if string(before) != string(got) {
+			t.Fatalf("the request changed:\nbefore %s\nafter  %s", before, got)
+		}
+	}
+}
+
+// What the build seat's verdict says of its siblings reaches the forge's holder in the controller's `checked`.
+func TestTheVerdictCarriesTheSiblingsAndWhereTheJudgeCameFrom(t *testing.T) {
+	read := []link.CheckSibling{{Repository: "novox/mesh-controller", Number: 346, Head: headController, Base: "main", BaseCommit: headHost}}
+	c := checkedOf(link.BuildResult{ID: "b", Ref: headHost, Checked: &link.CheckRequest{Owner: "novox", Repo: "mesh-host", Number: 114},
+		Check: &link.CheckOutcome{Verdict: "pass", Summary: "ok", Siblings: read, JudgeFrom: "sibling novox/mesh-controller#346 merge abc",
+			Validator: "the change's own validator"}})
+	if len(c.Siblings) != 1 || c.Siblings[0] != read[0] || c.JudgeFrom == "" || c.Validator == "" {
+		t.Fatalf("the verdict says %+v", c)
+	}
+	body, _ := json.Marshal(c)
+	for _, want := range []string{`"siblings":[{"repository":"novox/mesh-controller","number":346,"head":"` + headController +
+		`","base":"main","base_commit":"` + headHost + `"}]`, `"judge_from":"sibling novox/mesh-controller#346 merge abc"`} {
+		if !strings.Contains(string(body), want) {
+			t.Fatalf("the verdict lacks %s:\n%s", want, body)
+		}
+	}
+	unknown := checkedOf(link.BuildResult{ID: "b", Check: &link.CheckOutcome{Verdict: "pass", SiblingsUnknown: "mesh-delivery did not answer"}})
+	if body, _ := json.Marshal(unknown); !strings.Contains(string(body), `"siblings_unknown":"mesh-delivery did not answer"`) ||
+		strings.Contains(string(body), `"siblings":`) {
+		t.Fatalf("the verdict that could not learn them says %s", body)
+	}
+}

cmd/mesh-controller/check_test.go

@@ -0,0 +1,161 @@
+package main
+
+import (
+	"bytes"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/beside"
+	"github.com/novox/mesh-controller/internal/catalogue"
+)
+
+// The check anybody can run is the check registration runs (novox/hq issue 148, ADR 0037): a manifest
+// with a known fault is named, and one without passes, with no store opened.
+func TestModuleCheckNamesAFaultAndNeedsNoMesh(t *testing.T) {
+	dir := t.TempDir()
+	good := filepath.Join(dir, "good.json")
+	bad := filepath.Join(dir, "bad.json")
+	os.WriteFile(good, []byte(`{"module":"shop","version":"1","tools":["price"],"invokes":["mesh-catalog.catalog_modules"]}`), 0o600)
+	os.WriteFile(bad, []byte(`{"module":"till","version":"1","invokes":["shop"]}`), 0o600)
+
+	var out bytes.Buffer
+	if err := moduleCheck([]string{good}, &out); err != nil {
+		t.Fatalf("a sound manifest was refused: %v\n%s", err, out.String())
+	}
+	if !strings.Contains(out.String(), "shop: ok, 1 tool(s), invokes mesh-catalog.catalog_modules") {
+		t.Fatalf("the report does not say what it checked:\n%s", out.String())
+	}
+
+	out.Reset()
+	err := moduleCheck([]string{good, bad}, &out)
+	if err == nil {
+		t.Fatal("a manifest invoking a module and no tool passed")
+	}
+	if !strings.Contains(out.String(), `till invokes "shop", which does not name a tool`) {
+		t.Fatalf("the fault is not named in the manifest's words:\n%s", out.String())
+	}
+}
+
+// The rules between manifests run over what was given together: a seat two modules declare is
+// refused, which no single-manifest check can see.
+func TestModuleCheckJudgesBetweenTheManifestsGiven(t *testing.T) {
+	dir := t.TempDir()
+	a := filepath.Join(dir, "a.json")
+	b := filepath.Join(dir, "b.json")
+	os.WriteFile(a, []byte(`{"module":"a","version":"1","seats":[{"name":"printer","scope":"mesh"}]}`), 0o600)
+	os.WriteFile(b, []byte(`{"module":"b","version":"1","seats":[{"name":"printer","scope":"mesh"}]}`), 0o600)
+	var out bytes.Buffer
+	if err := moduleCheck([]string{a, b}, &out); err == nil {
+		t.Fatalf("two declarations of one seat passed:\n%s", out.String())
+	}
+	if !strings.Contains(out.String(), "a seat name means one protocol") {
+		t.Fatalf("the cross-manifest rule was not the one named:\n%s", out.String())
+	}
+}
+
+// The real catalogue passes the command, the way it passes the test that used to be the only check.
+func TestModuleCheckPassesTheCatalogue(t *testing.T) {
+	root := beside.Catalogue(t)
+	paths, err := manifestsUnder(root)
+	if err != nil || len(paths) == 0 {
+		t.Fatalf("no manifests under %s: %v", root, err)
+	}
+	var out bytes.Buffer
+	if err := moduleCheck(paths, &out); err != nil {
+		t.Fatalf("the catalogue does not pass its own check: %v\n%s", err, out.String())
+	}
+}
+
+func TestRegistrationRefusesADefinitionNamingAnInstallation(t *testing.T) {
+	// novox/hq ADR 0155: the check moves to registration once the catalogue passes it. Both
+	// ways in — `module add` and a build's result — go through this, and a name declared on
+	// purpose passes with its reason.
+	named := catalogue.Manifest{Module: "idp", Resources: []map[string]any{
+		{"id": "server", "type": "container", "image": "x@sha256:aa",
+			"env": map[string]any{"KC_HOSTNAME": "https://login.mesh-one.be"}},
+	}}
+	err := namesNoInstallation(named)
+	if err == nil || !strings.Contains(err.Error(), "login.mesh-one.be") ||
+		!strings.Contains(err.Error(), catalogue.NamesOnPurpose) {
+		t.Fatalf("a definition naming an installation is refused with the name and the way out; got %v", err)
+	}
+	meant := catalogue.Manifest{Module: "site", Resources: []map[string]any{
+		{"id": "server", "type": "container", "image": "registry.mesh-one.be/org/site@sha256:cc",
+			catalogue.NamesOnPurpose: map[string]any{
+				"registry.mesh-one.be": "built outside the mesh until its repository is a build source here"}},
+	}}
+	if err := namesNoInstallation(meant); err != nil {
+		t.Fatalf("a name declared on purpose passes; got %v", err)
+	}
+}
+
+// **The controller's own manifest names every verb of its seat** (novox/hq ADR 0132): its tools lagged
+// the seat's verbs for weeks, and `module check` — the gate's first step for a change touching it —
+// refused it. Held here, so a verb added to the table without the manifest fails this repository's
+// own suite rather than its next pull request's gate.
+func TestTheControllersManifestServesEveryVerbOfItsSeat(t *testing.T) {
+	var out strings.Builder
+	if err := moduleCheck([]string{"../../module.json"}, &out); err != nil {
+		t.Fatalf("the controller's own module.json fails module check: %v\n%s", err, out.String())
+	}
+}
+
+// A module that uses a seat another module declares (novox/hq issue 364): refused over the whole catalogue when the
+// declarer is missing, a note when the gate says it gives only the manifests a change touches.
+func TestASeatAnotherModuleDeclaresIsANoteOverSomeManifests(t *testing.T) {
+	dir := t.TempDir()
+	user := filepath.Join(dir, "user.json")
+	os.WriteFile(user, []byte(`{"module":"asker","version":"1","uses":["operator-channel"]}`), 0o600)
+	var out bytes.Buffer
+	if err := moduleCheck([]string{user}, &out); err == nil {
+		t.Fatalf("a use of a seat nothing given declares passed the whole-catalogue check:\n%s", out.String())
+	}
+	t.Setenv(SomeManifestsVar, "1")
+	out.Reset()
+	if err := moduleCheck([]string{user}, &out); err != nil {
+		t.Fatalf("over some manifests the use was refused:\n%s", out.String())
+	}
+	if !strings.Contains(out.String(), "note: asker uses the seat \"operator-channel\"") {
+		t.Fatalf("the note was not said:\n%s", out.String())
+	}
+}
+
+// **A module lives whole in one repository** (novox/hq ADR 0420 §1, issue 1019): `module check`, told the
+// repository it runs for, refuses an artifact whose build context names another; run by hand, it does not know.
+func TestModuleCheckRefusesAnArtifactContextNamingAnotherRepository(t *testing.T) {
+	dir := t.TempDir()
+	write := func(name, context string) string {
+		path := filepath.Join(dir, name+".json")
+		raw := `{"module":"` + name + `","version":"1","build":{"artifacts":[{"name":"server","kind":"image","from":"Dockerfile"` + context + `}]}}`
+		if err := os.WriteFile(path, []byte(raw), 0o600); err != nil {
+			t.Fatal(err)
+		}
+		return path
+	}
+	other := write("other", `,"context":{"seat":"git","repository":"novox/mesh-controller","ref":"main"}`)
+	own := write("own", `,"context":{"seat":"git","repository":"novox/mesh-catalog","ref":"main"}`)
+	none := write("none", ``)
+
+	t.Setenv("MESH_CHECK_REPOSITORY", "novox/mesh-catalog")
+	var out bytes.Buffer
+	if err := moduleCheck([]string{other}, &out); err == nil {
+		t.Fatalf("a context naming another repository passed:\n%s", out.String())
+	}
+	if !strings.Contains(out.String(), "other builds artifact server from novox/mesh-controller: a module lives whole in one repository (novox/hq ADR 0420 §1)") {
+		t.Errorf("the refusal is not in the words of the gate:\n%s", out.String())
+	}
+	for _, path := range []string{own, none} {
+		out.Reset()
+		if err := moduleCheck([]string{path}, &out); err != nil {
+			t.Errorf("%s was refused: %v\n%s", path, err, out.String())
+		}
+	}
+	t.Setenv("MESH_CHECK_REPOSITORY", "")
+	out.Reset()
+	if err := moduleCheck([]string{other}, &out); err != nil {
+		t.Errorf("a local run, with no repository named, refused it: %v\n%s", err, out.String())
+	}
+}

cmd/mesh-controller/checks.go

@@ -0,0 +1,663 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"path"
+	"regexp"
+	"runtime/debug"
+	"slices"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// A pull request's merge check (novox/hq to-be 45 §9, ADR 0237 as amended 2026-10-06): the forge
+// announces every pull request's new head, the controller decides what is checked, asks the build seat to
+// check it, and says the verdict as `checked`, which the forge's holder sets as the pull request's
+// statuses. **Before merge, never after**: every check the mesh had ran after a merge, on a machine.
+//
+// **The mesh's module graph decides, not the repository.** The controller holds the graph — every module,
+// the repository and directory it is built from — and maps the pull request's changed paths onto it by
+// the planner's own answer (reachOfMerge, touchedBy — the one place a changed file is mapped onto modules,
+// for the merge handler, the release planner, the merge gate and this check; issue 280): **a changed file
+// touches exactly the modules whose build reads it** — a module's own directory (the whole repository for
+// one built from its root), or a repository its recipe packages. A file no build reads — a script at the
+// root, a README — touches no module. A directory the change adds a module.json in, which the graph does
+// not hold yet (said by the head, issue 278), is a new module and is checked too.
+//
+//   - touches a module: the build seat runs **the gate** — `mesh/merge-gate`, the touched manifests, every
+//     machine composed with the change, the replays — and the repository's own merge-check.sh beside it;
+//   - touches none, in a repository that is the mesh's (it sources a module on some branch, or shares the
+//     core's owner): the gate is a pass that says so — a fact, not a missing check — and the repository's
+//     own merge-check.sh runs as `mesh/repo-check`, a warning when it has none;
+//   - touches none, anywhere else: the gate is a pass that says so, and nothing more is said.
+//
+// What is checked is decided here and run there (internal/builder/check.go).
+
+// checkTimeout is how long one check may run on the build seat. Said here so the ask's watchdog (S6)
+// and the builder agree on what late means.
+const checkTimeout = 45 * time.Minute
+
+// noModuleTouched is the gate's word for a change that touches nothing of the graph.
+const noModuleTouched = "the change touches no module of the mesh's graph"
+
+// noMergeCheck is the repository layer's word for a repository of the mesh with no merge-check.sh.
+const noMergeCheck = "the repository declares no merge-check.sh: none of its own tests run before it merges"
+
+// coreModules are the modules whose repositories are the mesh's core, by the directory a check finds
+// each beside it — and whose owner is the mesh's own.
+var coreModules = map[string]string{"mesh-controller": "mesh-controller", "mesh-host": "mesh-host",
+	"node-tools": "mesh-tools", "nats": "mesh-catalog"}
+
+// checkScope is what a pull request reaches of the mesh's graph, as the planner reckons it.
+type checkScope struct {
+	// Modules are the modules a merge of the change would move itself — built from the repository into
+	// the pull request's base and reading a changed file, or packaging the repository's source — and
+	// Dependents those the plan would build after them; New the directories it adds a module in.
+	Modules    []string
+	Dependents []string
+	New        []string
+	// Manifests are the moved modules' and the new ones' manifests in the change's tree.
+	Manifests []string
+	// Width is how many modules a merge would build, in how many tiers; Unread the changed files no
+	// module's build reads.
+	Width, Tiers int
+	Unread       []string
+	// Mesh says the repository is the mesh's: modules are built from it on some branch, its owner is the
+	// core's, or the change adds a module to it.
+	Mesh bool
+	// Judge is who judges the gate (link.JudgeSelf, link.JudgeValidator, or the running controller).
+	Judge string
+	// From is a module built from the repository, for how the mesh clones it; nil when none is.
+	From *inventory.Entry
+	// Reach is the planner's whole answer, which the change plan is made from.
+	Reach mergeReach
+}
+
+func (s checkScope) gated() bool { return len(s.Modules)+len(s.New) > 0 }
+
+// pullScope is what a pull request reaches: **the planner's own answer** (reachOfMerge), asked as if the
+// head were merged into the base — never a mapping of its own, so a change to what a merge touches
+// changes what is checked with it (novox/hq ADR 0238).
+func pullScope(p link.PullUpdated, entries []inventory.Entry, read map[string][]inventory.ReadRepository,
+	edges []inventory.Edge) checkScope {
+	m := link.SourceMoved{Owner: p.Owner, Repo: p.Repo, Base: p.Base, CloneURL: p.CloneURL, Commit: p.Commit,
+		Paths: p.Paths, PathsTruncated: p.PathsTruncated, Removed: p.Removed, ModuleDirs: p.ModuleDirs,
+		ModuleDirsSaid: p.ModuleDirsSaid}
+	r := reachOfMerge(m, entries, read, edges)
+	s := checkScope{Modules: r.Moved(), Dependents: r.Dependents(), New: r.Added, Unread: r.Unread,
+		Width: len(r.Plan.Modules), Tiers: len(r.Plan.Tiers), Reach: r}
+	for _, e := range append(append([]inventory.Entry{}, r.Touched...), r.Deleted...) {
+		s.Manifests = append(s.Manifests, path.Join(strings.Trim(e.Source.Path, "/"), moduleManifestFile))
+		switch e.Manifest.Module {
+		case "mesh-controller":
+			s.Judge = link.JudgeSelf
+		case "mesh-host":
+			if s.Judge == "" {
+				s.Judge = link.JudgeValidator
+			}
+		}
+	}
+	for _, d := range r.Added {
+		s.Manifests = append(s.Manifests, path.Join(d, moduleManifestFile))
+	}
+	sort.Strings(s.Manifests)
+	s.Manifests = slices.Compact(s.Manifests)
+
+	// Whose repository it is, for how it is cloned and whether its own check is the mesh's to run.
+	owners := map[string]bool{}
+	for i, e := range entries {
+		if e.Provided {
+			continue
+		}
+		if _, core := coreModules[e.Manifest.Module]; core {
+			if owner := sourceOwner(e.Source.Repository); owner != "" {
+				owners[owner] = true
+			}
+		}
+		if sameRepository(e.Source.Repository, m) && s.From == nil {
+			s.From = &entries[i]
+		}
+	}
+	s.Mesh = s.From != nil || owners[strings.ToLower(p.Owner)] || s.gated()
+	return s
+}
+
+// sourceOwner is the owner of a recorded repository, a path on the git seat or a URL: novox/mesh-host → novox.
+func sourceOwner(repository string) string {
+	parts := strings.Split(strings.Trim(strings.TrimSuffix(repository, ".git"), "/"), "/")
+	if len(parts) < 2 {
+		return ""
+	}
+	return strings.ToLower(parts[len(parts)-2])
+}
+
+// PullUpdated decides a pull request's merge check, and asks for it when there is something to run.
+func (f following) PullUpdated(ctx context.Context, p link.PullUpdated) error {
+	inv := f.open.inventory
+	entries, err := inv.Catalogued(ctx)
+	if err != nil {
+		return err
+	}
+	read, err := readForPlanning(ctx, inv)
+	if err != nil {
+		return err
+	}
+	edges, err := inv.Dependencies(ctx)
+	if err != nil {
+		return err
+	}
+	scope := pullScope(p, entries, read, edges)
+	// **A cycle of edges fails the check, naming every module and edge** (novox/hq ADR 0419 clause 6), a lone pull
+	// request's as a group's composed check is: no order exists for what it changes.
+	alone := orderMember{ID: p.Owner + "/" + p.Repo + "@" + twelve(p.Commit), Repository: p.Owner + "/" + p.Repo, Base: p.Base,
+		Head: p.Commit, Number: p.Number, Paths: p.Paths, PathsTruncated: p.PathsTruncated, Removed: p.Removed, BaseSHA: p.BaseSHA}
+	if failing, cyclic, err := cycleVerdict(ctx, "", []orderMember{alone},
+		map[string]orderReach{alone.ID: {Moved: scope.Modules}}, edges, entries); err != nil {
+		return err
+	} else if cyclic {
+		failing.Commit, failing.Trunk = p.Commit, twelve(p.BaseSHA)
+		fmt.Printf("%s/%s#%d (%.8s): %s\n", p.Owner, p.Repo, p.Number, p.Commit, failing.Summary)
+		sayChecked(ctx, failing)
+		return nil
+	}
+	// **A member of a group whose gate is the composed check's runs its repository's check alone** (novox/hq ADR 0403
+	// clause 1): mesh-delivery is asked once, and says so on the group's line. Told nothing, the pull request is
+	// checked alone, gate included (clause 6).
+	lines, groupsErr := groupsAsked(ctx, deliverySeatHeld(entries))
+	composed := groupsErr == nil && composedMember(p, lines)
+	// The change plan of the commit at hand (ADR 0238): what a merge of it would build and send, posted
+	// with the verdict whatever the verdict is.
+	plan := changePlanOf(p.Owner+"/"+p.Repo, p.Base, p.Commit, scope.Reach, entries, func(module string) (inventory.Upgrade, bool) {
+		u, err := inv.UpgradeOf(ctx, module)
+		return u, err == nil
+	})
+	fmt.Print(planText(plan))
+	direct := directVerdict(p, plan)
+	if composed {
+		scope.Modules, scope.Dependents, scope.New, scope.Manifests = nil, nil, nil, nil
+		composedGate(&direct)
+	}
+	switch {
+	case !scope.gated() && !scope.Mesh:
+		fmt.Printf("%s/%s#%d (%.8s): %s, and the repository is not the mesh's: said, nothing run\n",
+			p.Owner, p.Repo, p.Number, p.Commit, noModuleTouched)
+		sayChecked(ctx, direct)
+		return nil
+	case !scope.gated() && p.MergeCheckSaid && !p.MergeCheck:
+		direct.RepoCheck = &link.CheckLayer{Verdict: "warning", Summary: noMergeCheck}
+		fmt.Printf("%s/%s#%d (%.8s): %s; %s\n", p.Owner, p.Repo, p.Number, p.Commit, noModuleTouched, noMergeCheck)
+		sayChecked(ctx, direct)
+		return nil
+	}
+	request, err := checkRequestFor(ctx, f.open, p, scope, entries)
+	if err != nil {
+		return err
+	}
+	request.Check.Plan = &plan
+	request.Check.Composed = composed
+	// **The group's other open pull requests are read beside it** (novox/hq ADR 0382 §1).
+	siblingsFrom(&request, p, entries, lines, groupsErr)
+	seat := buildSeatHeld(ctx)
+	ask, err := askOverOn(seat)
+	if err != nil {
+		return err
+	}
+	defer ask.Close()
+	if err := ask.Ask(ctx, request); err != nil {
+		return err
+	}
+	// **A newer request replaces the one still waiting, and a newer key stops the one running** (novox/hq ADR 0406 §3, §4,
+	// issue 974): the check queue keeps one request a pull request, and a running check watches its key. Nothing is asked
+	// of the forge here (issue 726).
+	what := "its own merge-check.sh alone: " + noModuleTouched
+	if composed {
+		what = "its own merge-check.sh alone: the gate is its group's composed check's"
+	}
+	if scope.gated() {
+		what = fmt.Sprintf("the gate over %s (a merge would build %d module(s) in %d tier(s))",
+			strings.Join(append(append([]string{}, scope.Modules...), prefixedAll("new:", scope.New)...), ", "),
+			scope.Width, scope.Tiers)
+	}
+	fmt.Printf("%s/%s#%d (%.8s): asked %s to check it before it merges — %s — as %s\n", p.Owner, p.Repo, p.Number,
+		p.Commit, seat, what, request.ID)
+	return nil
+}
+
+// composedWords is what a group member's own verdict says of its gate layer (novox/hq ADR 0403 clause 1).
+const composedWords = "judged by its group's composed check"
+
+// gateComposed is a gate layer's verdict when no gate was run for the member alone: never a pass. Mesh-delivery reads it
+// as the composed check's to judge, and the forge's holder sets no mesh/merge-gate from it.
+const gateComposed = "composed"
+
+// composedGate says a group member's own verdict has no gate of its own: its gate layer, and the verdict that is
+// the gate's, read "composed" in place of a pass.
+func composedGate(c *link.Checked) {
+	c.Verdict, c.Summary = gateComposed, composedWords
+	c.Gate = &link.CheckLayer{Verdict: gateComposed, Summary: composedWords}
+}
+
+// directVerdict is the verdict of a change no build judges — it touches no module, and either the repository is not
+// the mesh's or the head holds no merge-check.sh. **It names the trunk commit it holds for** (novox/hq ADR 0323 §3):
+// the base branch's head the forge announced with the head, so the merge tool can weigh it against the trunk's head
+// and does not refuse it for ever (a verdict naming no trunk is never the trunk's head's). Nothing was built to
+// judge: the trunk commit is the one the forge said the change was announced against.
+func directVerdict(p link.PullUpdated, plan link.ChangePlan) link.Checked {
+	trunk := p.BaseSHA
+	if len(trunk) > 12 {
+		trunk = trunk[:12]
+	}
+	if trunk != "" {
+		plan.Trunk = trunk
+	}
+	return link.Checked{Owner: p.Owner, Repo: p.Repo, Number: p.Number, Commit: p.Commit,
+		ID: link.NewBuildID(time.Now()), Verdict: "pass", Summary: noModuleTouched,
+		Gate: &link.CheckLayer{Verdict: "pass", Summary: noModuleTouched}, Plan: &plan, Trunk: trunk}
+}
+
+// checkRequestFor is the ask for one pull request's head: the repository as the mesh clones it, the head,
+// and what is read beside it.
+func checkRequestFor(ctx context.Context, open *stores, p link.PullUpdated, scope checkScope,
+	entries []inventory.Entry) (link.BuildRequest, error) {
+	shelf := map[string]catalogue.Manifest{}
+	for _, e := range entries {
+		shelf[e.Manifest.Module] = e.Manifest
+	}
+	world, err := theRestOfTheMesh(ctx, open.inventory, shelf, "")
+	if err != nil {
+		return link.BuildRequest{}, err
+	}
+	clone := func(s inventory.Source) (string, error) {
+		if s.Seat == "" {
+			return s.Repository, nil
+		}
+		return clonedFromSeat(world, s.Seat, s.Repository)
+	}
+	// As the mesh clones a module built from it; a repository no module is built from, from the forge.
+	source := inventory.Source{Seat: gitSeat, Repository: p.Owner + "/" + p.Repo}
+	if scope.From != nil {
+		source = scope.From.Source
+	}
+	repository, err := clone(source)
+	if err != nil {
+		return link.BuildRequest{}, err
+	}
+	current, err := open.inventory.CurrentBuilds(ctx)
+	if err != nil {
+		return link.BuildRequest{}, err
+	}
+	beside, err := besideOf(entries, func(module string) string { return current[module].Commit }, clone)
+	if err != nil {
+		return link.BuildRequest{}, err
+	}
+	builds := checkBuildsOf(p, scope, entries, clone)
+	return link.BuildRequest{
+		ID:         link.NewBuildID(time.Now()),
+		Repository: repository,
+		Ref:        p.Commit,
+		Held:       heldBy(ctx),
+		Seats:      seatBases(ctx),
+		Source:     sourceOnSeat(source),
+		Check: &link.CheckRequest{Owner: p.Owner, Repo: p.Repo, Number: p.Number, Base: p.Base, Trunk: p.BaseSHA, Ready: p.Ready,
+			Paths: p.Paths, Beside: beside, Modules: scope.Modules, Dependents: scope.Dependents, New: scope.New,
+			Manifests: scope.Manifests, Judge: scope.Judge, Builds: builds, Named: namedForTheCheck(ctx, p, builds),
+			Running: runningBy(ctx)},
+	}, nil
+}
+
+// besideOf is what a check reads beside its own repository, by the directory it is found under: each core repository
+// by the module the mesh builds from it, at besideRefs. running is the commit the mesh runs of a module.
+func besideOf(entries []inventory.Entry, running func(module string) string,
+	clone func(inventory.Source) (string, error)) (map[string]link.CheckedOut, error) {
+	beside := map[string]link.CheckedOut{}
+	for _, e := range entries {
+		dir, core := coreModules[e.Manifest.Module]
+		if !core || e.Provided || e.Source.Repository == "" {
+			continue
+		}
+		url, err := clone(e.Source)
+		if err != nil {
+			return nil, err
+		}
+		refs := besideRefs(dir, running(e.Manifest.Module))
+		beside[dir] = link.CheckedOut{Repository: url, Ref: refs[dir]}
+		if dir == "mesh-controller" {
+			// The controller's main stays its main: it judges only a check the running controller predates.
+			beside["mesh-controller-main"] = link.CheckedOut{Repository: url, Ref: refs["mesh-controller-main"]}
+			if e.Source.Seat != "" {
+				for _, sibling := range []string{"mesh-lab", "mesh-sdk"} {
+					if url, err := clone(inventory.Source{Seat: e.Source.Seat, Repository: siblingOf(e.Source.Repository,
+						sibling)}); err == nil {
+						beside[sibling] = link.CheckedOut{Repository: url, Ref: refs[sibling]}
+					}
+				}
+			}
+		}
+	}
+	return beside, nil
+}
+
+// trunkOf is the branch a module's source follows: main when it records none, or records a commit.
+func trunkOf(s inventory.Source) string {
+	if t := strings.TrimSpace(followedBranch(s.Ref)); t != "" {
+		return t
+	}
+	return "main"
+}
+
+// sourceName is the name of a recorded repository, a path on the git seat or a URL: novox/mesh-host → mesh-host.
+func sourceName(repository string) string {
+	parts := strings.Split(strings.Trim(strings.TrimSuffix(repository, ".git"), "/"), "/")
+	if len(parts) < 2 {
+		return ""
+	}
+	return parts[len(parts)-1]
+}
+
+// namedForTheCheck are the builds earlier checks of the same pull request at the same head named, read once for the
+// check (novox/hq issue 703): asked again because only the trunk moved, the check keeps what they built of a key
+// still the same. Another pull request's build, or one of an earlier head, is never kept. None when they cannot be
+// read, and the check builds, as before.
+func namedForTheCheck(ctx context.Context, p link.PullUpdated, builds []link.CheckBuild) []link.CheckedBuild {
+	if len(builds) == 0 || p.Commit == "" {
+		return nil
+	}
+	pull := link.PullRef{Owner: p.Owner, Repo: p.Repo, Number: p.Number}
+	read, err := checkedBuildsOf(ctx, []link.PullRef{pull})
+	if err != nil {
+		fmt.Printf("  the earlier checks' builds of %s/%s#%d could not be read, so the check builds: %v\n",
+			p.Owner, p.Repo, p.Number, err)
+		// empty-on-error: said above; a check handed no named build builds every module, as before issue 703
+		return nil
+	}
+	var named []link.CheckedBuild
+	for _, b := range read {
+		if b.Pull == pull && link.SameHead(b.Head, p.Commit) {
+			named = append(named, b)
+		}
+	}
+	return named
+}
+
+// checkBuildsOf are the modules a merge of the change would build, in the walk's order, as the check builds them
+// for the walk to take (novox/hq ADR 0350 §1): a module built from the repository checked, at the branch it merges
+// into, from the merge the check makes; any other — a module standing on one — from its own repository at the
+// branch it follows, as the walk builds it. A module whose build reads the repository checked through a context,
+// or that the merge deletes, cannot be built as the walk would: said, and nothing after it is built. A change that
+// moves no module builds nothing.
+func checkBuildsOf(p link.PullUpdated, scope checkScope, entries []inventory.Entry,
+	clone func(inventory.Source) (string, error)) []link.CheckBuild {
+	if len(scope.Reach.Plan.Tiers) == 0 {
+		return nil
+	}
+	m := link.SourceMoved{Owner: p.Owner, Repo: p.Repo, Base: p.Base, CloneURL: p.CloneURL}
+	byName := map[string]inventory.Entry{}
+	for _, e := range entries {
+		byName[e.Manifest.Module] = e
+	}
+	skip := map[string]string{}
+	for _, e := range scope.Reach.Packaging {
+		skip[e.Manifest.Module] = "its build reads " + p.Owner + "/" + p.Repo + " through a context, which a check " +
+			"cannot hand the merge"
+	}
+	for _, e := range scope.Reach.Deleted {
+		skip[e.Manifest.Module] = "the merge deletes it"
+	}
+	var out []link.CheckBuild
+	for tier, names := range scope.Reach.Plan.Tiers {
+		for _, name := range names {
+			e, known := byName[name]
+			b := link.CheckBuild{Module: name, Tier: tier, Skip: skip[name]}
+			switch {
+			case !known:
+				b.Skip = "the catalogue does not hold it"
+			case b.Skip != "":
+			case sourceIs(e.Source, m):
+				b.Merged, b.Path = true, e.Source.Path
+			default:
+				url, err := clone(e.Source)
+				if err != nil {
+					b.Skip = "its repository cannot be cloned: " + err.Error()
+					break
+				}
+				b.Repository, b.Path, b.Ref = url, e.Source.Path, followedBranch(e.Source.Ref)
+			}
+			out = append(out, b)
+		}
+	}
+	return out
+}
+
+// besideRefs is the ref each repository is cloned at beside a check, by the directory it is found under:
+// a core repository at the commit the mesh runs of the module built from it (`running`) — but the
+// catalogue, whose checkout beside is what tests read its files from, at its main, what the next merge
+// builds from; and beside the controller its main, for a judge the running controller predates, and the
+// lab's main, whose replays every check runs. **One rule, read by the check the controller asks for and by
+// the facts snapshot** (Facts.Beside), so a check run by hand clones what the build seat clones. Beside the
+// controller also the SDK, checked out at the commit the running controller's go.mod pins (sdkPinned), not
+// one a desktop holds (novox/hq issue 449). The checkout only places the clone: the conformance test reads the
+// fixtures at the pin of the tree under check, from the clone's history, so a pull request moving the SDK is
+// judged against the SDK it moves to (internal/link/conformance_test.go).
+func besideRefs(dir, running string) map[string]string {
+	switch dir {
+	case "mesh-catalog":
+		return map[string]string{dir: "main"}
+	case "mesh-controller":
+		return map[string]string{dir: running, "mesh-controller-main": "main", "mesh-lab": "main",
+			"mesh-sdk": sdkPinned()}
+	}
+	return map[string]string{dir: running}
+}
+
+// sdkModule is the Go module of the SDK the controller is built against.
+const sdkModule = "git.novox.be/novox/mesh-sdk/go"
+
+// pseudoCommit is the commit a Go pseudo-version names: v0.1.11-0.20261009143344-f047d0a4a970 → f047d0a4a970.
+var pseudoCommit = regexp.MustCompile(`-([0-9a-f]{12})$`)
+
+// sdkPinned is the ref of the SDK repository this controller was built from, as its go.mod pins it and its
+// build records it: a pseudo-version's commit, or a release's tag (the SDK tags its Go module under go/).
+// "main" only for a binary that records no SDK version — a local replace — which a running controller is
+// not (novox/hq issue 449).
+func sdkPinned() string {
+	info, ok := debug.ReadBuildInfo()
+	if !ok {
+		return "main"
+	}
+	for _, dep := range info.Deps {
+		if dep.Path != sdkModule {
+			continue
+		}
+		if dep.Replace != nil {
+			dep = dep.Replace
+		}
+		if m := pseudoCommit.FindStringSubmatch(dep.Version); m != nil {
+			return m[1]
+		}
+		if strings.HasPrefix(dep.Version, "v") {
+			return "go/" + dep.Version
+		}
+	}
+	return "main"
+}
+
+// siblingOf is another repository of the same owner: novox/mesh-controller → novox/mesh-lab.
+func siblingOf(repository, name string) string {
+	if cut := strings.LastIndex(repository, "/"); cut >= 0 {
+		return repository[:cut+1] + name
+	}
+	return name
+}
+
+// sourceOnSeat is a source's seat form, nil for one on no seat.
+func sourceOnSeat(s inventory.Source) *link.SourceOnSeat {
+	if s.Seat == "" {
+		return nil
+	}
+	return &link.SourceOnSeat{Seat: s.Seat, Repository: s.Repository}
+}
+
+// checkEvents is where the serving controller says a check's verdict; nil in a command.
+var checkEvents link.Bus
+
+// maxCheckReport is how much of a check's report travels in its verdict: enough for the failures and
+// the machines, never a log.
+const maxCheckReport = 60 << 10
+
+// checked says a merge check's verdict as the controller's `checked`. Nothing is recorded or
+// registered: a check builds nothing (issue 240's rule for a dry run, kept for a check).
+func checked(ctx context.Context, result link.BuildResult) {
+	// **A check stopped by its key says nothing** (novox/hq ADR 0406 §4, issue 974, review 2): it stopped because the head or
+	// the trunk commit moved on, and the newer request will judge. Said as an error it would name the live head — red
+	// statuses on the forge, a delivery refused — and written to the key it would stand in the newer request's way.
+	if result.Failed == link.SupersededByKey {
+		fmt.Printf("%s: stopped, its pull request's key moved on; the newer check will judge\n", result.ID)
+		return
+	}
+	sayChecked(ctx, checkedOf(result))
+}
+
+// checkedOf is what a check's outcome says: each layer, and an error — never a pass — for a check that
+// could not run.
+func checkedOf(result link.BuildResult) link.Checked {
+	c := link.Checked{ID: result.ID, On: result.On, Commit: result.Ref}
+	if result.Checked != nil {
+		c.Owner, c.Repo, c.Number = result.Checked.Owner, result.Checked.Repo, result.Checked.Number
+	}
+	switch {
+	case result.Check != nil:
+		c.Verdict, c.Summary, c.Report = result.Check.Verdict, result.Check.Summary, result.Check.Report
+		c.Gate, c.RepoCheck = result.Check.Gate, result.Check.RepoCheck
+		// What was judged (novox/hq ADR 0323 §3): the head merged into the trunk commit, and the commits of the
+		// repositories read beside it.
+		c.Trunk, c.Beside, c.Took = result.Check.Trunk, result.Check.Beside, result.Check.Took
+		c.Built = result.Check.Built
+		c.Validator = result.Check.Validator
+		c.Siblings, c.SiblingsUnknown, c.JudgeFrom = result.Check.Siblings, result.Check.SiblingsUnknown, result.Check.JudgeFrom
+		if c.Gate == nil {
+			// A build seat from before the layers: its verdict is the gate's.
+			c.Gate = &link.CheckLayer{Verdict: c.Verdict, Summary: c.Summary}
+		}
+	case result.Failed != "":
+		// The check could not run: an error, never read as a pass — on both layers it was asked for.
+		c.Verdict, c.Summary = "error", "the check could not run: "+firstLine(result.Failed)
+	default:
+		c.Verdict, c.Summary = "error", "the build seat answered the check with no verdict"
+	}
+	if c.Verdict == "" {
+		c.Verdict = "error"
+	}
+	if result.Check == nil {
+		c.Gate = &link.CheckLayer{Verdict: c.Verdict, Summary: c.Summary}
+		c.RepoCheck = &link.CheckLayer{Verdict: c.Verdict, Summary: c.Summary}
+	}
+	// **A group member's own check has no gate of its own** (novox/hq ADR 0403 clause 1): what ran was the repository's
+	// check alone, and its gate layer is "composed", never a pass. A failure or an error stays what it was.
+	if result.Checked != nil && result.Checked.Composed && result.Check != nil && c.Gate != nil &&
+		(c.Gate.Verdict == "pass" || c.Gate.Verdict == "warning") {
+		composedGate(&c)
+	}
+	if result.Checked != nil && c.Gate != nil && len(c.Gate.Modules) == 0 {
+		c.Gate.Modules = append(append([]string{}, result.Checked.Modules...), prefixedAll("new:", result.Checked.New)...)
+	}
+	if result.Checked != nil && c.Gate != nil && len(c.Gate.Dependents) == 0 {
+		c.Gate.Dependents = result.Checked.Dependents
+	}
+	if result.Checked != nil {
+		c.Plan = result.Checked.Plan
+		if c.Plan != nil && c.Trunk != "" {
+			// The kept delivery plan records the trunk commit with its other inputs (ADR 0323 §3).
+			plan := *c.Plan
+			plan.Trunk = c.Trunk
+			c.Plan = &plan
+		}
+		// A delivery group's composed check (novox/hq ADR 0239): every head it judged, this one first.
+		if g := result.Checked; g.Group != "" {
+			c.Group = g.Group
+			c.Members = append(c.Members, link.CheckedMember{Owner: g.Owner, Repo: g.Repo, Number: g.Number,
+				Commit: result.Ref, Trunk: c.Trunk})
+			for _, m := range g.Members {
+				c.Members = append(c.Members, link.CheckedMember{Owner: m.Owner, Repo: m.Repo, Number: m.Number,
+					Commit: m.Ref, Trunk: memberTrunk(result.Check, m)})
+			}
+		}
+	}
+	for _, l := range []*link.CheckLayer{c.Gate, c.RepoCheck} {
+		if l != nil && l.Verdict == "" {
+			l.Verdict = "error"
+		}
+	}
+	// **A check run again says so** (novox/hq issue 594). The summaries are the lines the pull request
+	// shows, clipped by the forge to a few words, so they get only a short marker after the verdict's own
+	// words; the report gets the whole sentence. Layers copied, so the build's own outcome is left as it came.
+	if mark := link.RunMarker(result.Delivery); mark != "" {
+		c.Summary += " " + mark
+		for _, l := range []**link.CheckLayer{&c.Gate, &c.RepoCheck} {
+			if *l != nil {
+				layer := **l
+				layer.Summary += " " + mark
+				*l = &layer
+			}
+		}
+		c.Report = link.Restarted(result.Delivery) + "\n\n" + c.Report
+	}
+	if len(c.Report) > maxCheckReport {
+		c.Report = "…" + c.Report[len(c.Report)-maxCheckReport:]
+	}
+	return c
+}
+
+// memberTrunk is the trunk commit the build seat merged one of a group's heads into (novox/hq ADR 0323 §6), empty
+// when it said none.
+func memberTrunk(outcome *link.CheckOutcome, m link.GroupMember) string {
+	if outcome == nil {
+		return ""
+	}
+	for _, j := range outcome.Members {
+		if strings.EqualFold(j.Owner, m.Owner) && strings.EqualFold(j.Repo, m.Repo) && strings.HasPrefix(m.Ref, j.Commit) {
+			return j.Trunk
+		}
+	}
+	return ""
+}
+
+func prefixedAll(prefix string, items []string) []string {
+	out := make([]string, 0, len(items))
+	for _, i := range items {
+		out = append(out, prefix+i)
+	}
+	return out
+}
+
+// sayChecked says a merge check's verdict on the bus, where the forge's holder hears it.
+func sayChecked(ctx context.Context, c link.Checked) {
+	repo := "none"
+	if c.RepoCheck != nil {
+		repo = strings.ToUpper(c.RepoCheck.Verdict) + " — " + c.RepoCheck.Summary
+	}
+	judged := ""
+	if c.Trunk != "" {
+		judged = " merged into trunk " + c.Trunk
+	}
+	fmt.Printf("%s: %s/%s#%d at %.8s%s checked on %s: gate %s — %s; repository %s\n", c.ID, c.Owner, c.Repo, c.Number,
+		c.Commit, judged, orSomewhere(c.On), strings.ToUpper(c.Verdict), c.Summary, repo)
+	if checkEvents == nil {
+		return
+	}
+	body, err := json.Marshal(c)
+	if err != nil {
+		return
+	}
+	stating, stop := context.WithTimeout(context.WithoutCancel(ctx), 10*time.Second)
+	defer stop()
+	if err := checkEvents.PublishSeatEvent(stating, link.MeshControllerSeat, link.KeyChecked, body); err != nil {
+		fmt.Printf("%s: the verdict could not be said, so the pull request is not told it: %v\n", c.ID, err)
+	}
+}

cmd/mesh-controller/checks_integration_test.go

@@ -0,0 +1,56 @@
+//go:build integration
+
+package main
+
+import (
+	"encoding/json"
+	"testing"
+	"time"
+
+	"github.com/nats-io/nats.go"
+	"github.com/novox/mesh-controller/internal/broker"
+	"github.com/novox/mesh-controller/internal/link"
+	"github.com/novox/mesh-controller/internal/testbus"
+)
+
+func TestACheckStoppedByItsKeyIsAnnouncedAsNoVerdict(t *testing.T) {
+	js, err := broker.Dial(testbus.URL(t))
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(js.Close)
+	if err := broker.AssertMeshStreams(js); err != nil {
+		t.Fatal(err)
+	}
+	legacy, err := js.Conn().JetStream()
+	if err != nil {
+		t.Fatal(err)
+	}
+	was := checkEvents
+	checkEvents = link.OverNATS{Conn: js.Conn(), JS: legacy}
+	t.Cleanup(func() { checkEvents = was })
+	heard := make(chan *nats.Msg, 4)
+	sub, err := js.Conn().ChanSubscribe(link.SeatEventSubject(link.MeshControllerSeat, link.KeyChecked), heard)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer func() { _ = sub.Unsubscribe() }()
+	asked := &link.CheckRequest{Owner: "novox", Repo: "mesh-catalog", Number: 3}
+	checked(t.Context(), link.BuildResult{ID: "stopped", Ref: "abc", Checked: asked, Failed: link.SupersededByKey})
+	checked(t.Context(), link.BuildResult{ID: "broken", Ref: "abc", Checked: asked, Failed: "the facts snapshot cannot be read"})
+	select {
+	case m := <-heard:
+		var c link.Checked
+		_ = json.Unmarshal(m.Data, &c)
+		if c.ID != "broken" || c.Verdict != "error" {
+			t.Fatalf("the first verdict said is %+v; want only the broken check's error", c)
+		}
+	case <-time.After(5 * time.Second):
+		t.Fatal("nothing was said")
+	}
+	select {
+	case m := <-heard:
+		t.Fatalf("a second verdict was said: %s", m.Data)
+	case <-time.After(300 * time.Millisecond):
+	}
+}

cmd/mesh-controller/checks_queue_test.go

@@ -0,0 +1,97 @@
+//go:build integration
+
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"testing"
+
+	"github.com/nats-io/nats.go"
+
+	"github.com/novox/mesh-controller/internal/broker"
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// Acceptance 5 of milestone 2 (novox/hq ADR 0406 §3, issue 974), live, with the store and a real bus: two merges into one
+// repository within a minute, with two open pull requests, leave each pull request with exactly one queued check, by the
+// stream's rule. Each merge moves the trunk, and mesh-delivery asks the controller to check both open pull requests again
+// against it (`delivery check`, which is the controller's own path for a head announced); nothing moves a request, nothing
+// asks the forge, and the queue is read back whole.
+func TestTwoMergesWithinAMinuteLeaveEachOpenPullRequestOneQueuedCheck(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	js, _ := aBuildQueue(t)
+	servingBus.Store(js)
+	t.Cleanup(func() { servingBus.Store(nil) })
+	holdTheDeliverySeat(t, open)
+	was := askDeliveryOwner
+	t.Cleanup(func() { askDeliveryOwner = was })
+	askDeliveryOwner = func(_ context.Context, _ *nats.Conn, verb string, _ map[string]any) (json.RawMessage, error) {
+		if verb != "groups" {
+			t.Fatalf("asked the owner %s", verb)
+		}
+		return json.RawMessage(`[]`), nil
+	}
+	// The repository the two pull requests are into, as a module the mesh builds from it.
+	if err := open.inventory.RegisterModule(ctx, catalogue.Manifest{Module: "mesh-controller", Version: "1"},
+		inventory.Source{Repository: "novox/mesh-controller", Ref: "main", BuiltFrom: "c0", Head: "c0"}); err != nil {
+		t.Fatal(err)
+	}
+
+	heads := map[int]string{7: "7777777777777777777777777777777777777777", 8: "8888888888888888888888888888888888888888"}
+	check := func(number int, trunk string) {
+		t.Helper()
+		p := orderMember{ID: fmt.Sprintf("novox/mesh-controller@%.12s", heads[number]), Repository: "novox/mesh-controller",
+			Base: "main", Head: heads[number], Number: number, Paths: []string{"main.go"}, ModuleDirsSaid: true,
+			BaseSHA: trunk, Ready: number == 8}.pull()
+		p.MergeCheck, p.MergeCheckSaid = true, true
+		if err := (following{open: open, oneShot: true}).PullUpdated(ctx, p); err != nil {
+			t.Fatal(err)
+		}
+	}
+	// Announced against the trunk as it stands, then asked again after each of two merges.
+	for _, trunk := range []string{"1111111111111111111111111111111111111111", "2222222222222222222222222222222222222222",
+		"3333333333333333333333333333333333333333"} {
+		check(7, trunk)
+		check(8, trunk)
+	}
+
+	q, err := link.ReadQueue(ctx, js, link.TheBuildMachine)
+	if err != nil {
+		t.Fatal(err)
+	}
+	seen := map[int]string{}
+	for _, a := range q.Asks {
+		c := a.Request.Check
+		if c == nil {
+			t.Fatalf("%s is no check", a.ID)
+		}
+		if _, twice := seen[c.Number]; twice {
+			t.Errorf("pull request %d has two queued checks", c.Number)
+		}
+		seen[c.Number] = c.Trunk
+		if a.State != link.AskWaiting {
+			t.Errorf("%s is %s", a.ID, a.State)
+		}
+		if want := "3333333333333333333333333333333333333333"; c.Trunk != want {
+			t.Errorf("pull request %d is queued against %.8s; want the newest trunk %.8s", c.Number, c.Trunk, want)
+		}
+	}
+	if len(seen) != 2 {
+		t.Fatalf("queued checks for %v; want one for each of the two open pull requests", seen)
+	}
+	// By the streams' own count: the ready one on its stream, the other on its.
+	for stream, want := range map[string]uint64{broker.ChecksReadyStream: 1, broker.ChecksOtherStream: 1} {
+		info, err := js.Context().StreamInfo(stream)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if info.State.Msgs != want {
+			t.Errorf("%s holds %d request(s); want %d", stream, info.State.Msgs, want)
+		}
+	}
+}

cmd/mesh-controller/checks_test.go

@@ -0,0 +1,293 @@
+package main
+
+import (
+	"errors"
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// **The mesh's module graph decides what a pull request's check runs**, not the repository (novox/hq
+// ADR 0237 as amended): a change is mapped onto the graph by the rule a merge is (issue 278), the gate
+// runs when it touches a module — a new one included — and a repository that is the mesh's and touches
+// none still has its own merge-check.sh run.
+func TestThePullRequestIsMappedOntoTheModuleGraph(t *testing.T) {
+	const catalogue = "http://forge.internal:20000/novox/mesh-catalog.git"
+	const controller = "http://forge.internal:20000/novox/mesh-controller.git"
+	const host = "http://forge.internal:20000/novox/mesh-host.git"
+	photos := fromRepo("photos", "http://forge.internal:20000/novox/photos.git", "")
+	photos.Source.Ref = "nox-mesh"
+	snake := fromRepo("snake", "jschoubben/snake", "")
+	snake.Source.Seat = "git"
+	entries := []inventory.Entry{
+		fromRepo("gitea", catalogue, "modules/gitea"),
+		fromRepo("keycloak", catalogue, "modules/keycloak"),
+		fromRepo("nats", catalogue, "modules/nats"),
+		fromRepo("mesh-controller", controller, ""),
+		fromRepo("mesh-host", host, ""),
+		photos, snake,
+	}
+	pull := func(owner, repo, base string, paths []string, dirs ...string) link.PullUpdated {
+		return link.PullUpdated{Owner: owner, Repo: repo, Base: base, Commit: "abc", Paths: paths,
+			ModuleDirs: dirs, ModuleDirsSaid: true}
+	}
+	for _, c := range []struct {
+		what                   string
+		p                      link.PullUpdated
+		modules, new, manifest string
+		mesh                   bool
+		judge                  string
+	}{
+		{"one module's own files", pull("novox", "mesh-catalog", "main", []string{"modules/gitea/index.ts"}, "modules/gitea"),
+			"gitea", "", "modules/gitea/module.json", true, ""},
+		{"a file no module's build reads touches no module (issue 280)",
+			pull("novox", "mesh-catalog", "main", []string{"merge-check.sh", "README.md"}), "", "", "", true, ""},
+		{"files the announcer could not list: everything built from it",
+			link.PullUpdated{Owner: "novox", Repo: "mesh-catalog", Base: "main", Commit: "abc", PathsTruncated: true,
+				Paths: []string{"README.md"}}, "gitea,keycloak,nats", "",
+			"modules/gitea/module.json,modules/keycloak/module.json,modules/nats/module.json", true, ""},
+		{"a new module, said by the head", pull("novox", "mesh-catalog", "main",
+			[]string{"modules/newmod/index.ts", "modules/newmod/module.json"}, "modules/newmod"),
+			"", "modules/newmod", "modules/newmod/module.json", true, ""},
+		{"the controller judges itself", pull("novox", "mesh-controller", "main", []string{"cmd/x.go"}),
+			"mesh-controller", "", "module.json", true, "self"},
+		{"the node-engine is judged with its validator", pull("novox", "mesh-host", "main", []string{"validate/v.go"}),
+			"mesh-host", "", "module.json", true, "validator"},
+		{"the core's owner, no module: the mesh's, its own check alone", pull("novox", "hq", "main", []string{"README.md"}),
+			"", "", "", true, ""},
+		{"a branch nothing is built from: the mesh's repository, no module", pull("novox", "photos", "master",
+			[]string{"server/x.js"}), "", "", "", true, ""},
+		{"the branch a module is built from", pull("novox", "photos", "nox-mesh", []string{"server/x.js"}),
+			"photos", "", "module.json", true, ""},
+		{"a repository on the forge's seat", pull("jschoubben", "snake", "main", []string{"index.html"}),
+			"snake", "", "module.json", true, ""},
+		{"a repository of nobody's, touching nothing", pull("someone", "dotfiles", "main", []string{"x"}),
+			"", "", "", false, ""},
+		{"a repository adding a module at its root", pull("someone", "newapp", "main", []string{"module.json", "x.js"}),
+			"", ".", "module.json", true, ""},
+	} {
+		s := pullScope(c.p, entries, nil, nil)
+		got := []string{strings.Join(s.Modules, ","), strings.Join(s.New, ","), strings.Join(s.Manifests, ",")}
+		want := []string{c.modules, c.new, c.manifest}
+		for i, what := range []string{"modules", "new", "manifests"} {
+			if got[i] != want[i] {
+				t.Errorf("%s: %s %q, wanted %q", c.what, what, got[i], want[i])
+			}
+		}
+		if s.Mesh != c.mesh || s.Judge != c.judge {
+			t.Errorf("%s: the mesh's %v judged by %q, wanted %v by %q", c.what, s.Mesh, s.Judge, c.mesh, c.judge)
+		}
+		if s.gated() != (c.modules != "" || c.new != "") {
+			t.Errorf("%s: gated %v", c.what, s.gated())
+		}
+	}
+}
+
+// A module whose build packages another repository's source is touched by a change to it.
+func TestAPullRequestTouchesWhatPackagesItsRepository(t *testing.T) {
+	entries := []inventory.Entry{fromRepo("node-tools", "http://forge.internal:20000/novox/mesh-tools.git", "node-tools")}
+	read := map[string][]inventory.ReadRepository{"node-tools": {{Repository: "http://forge.internal:20000/novox/mesh-sdk.git"}}}
+	s := pullScope(link.PullUpdated{Owner: "novox", Repo: "mesh-sdk", Base: "main", Commit: "abc", Paths: []string{"go/x.go"}}, entries, read, nil)
+	if strings.Join(s.Modules, ",") != "node-tools" || len(s.Manifests) != 0 {
+		t.Fatalf("a change to what node-tools packages touched %v (manifests %v)", s.Modules, s.Manifests)
+	}
+}
+
+// Each layer is said; a check that could not run is an error on both, never a pass; a build seat from
+// before the layers is read as the gate.
+func TestAChecksLayersAreEachSaidAndAnErrorIsNeverAPass(t *testing.T) {
+	asked := &link.CheckRequest{Owner: "novox", Repo: "mesh-catalog", Number: 3, Modules: []string{"gitea"}}
+	c := checkedOf(link.BuildResult{ID: "b", Ref: "abc", Checked: asked, Failed: "the facts snapshot cannot be read"})
+	if c.Verdict != "error" || c.Gate == nil || c.Gate.Verdict != "error" || c.RepoCheck == nil || c.RepoCheck.Verdict != "error" {
+		t.Fatalf("a check that could not run said %+v", c)
+	}
+	if strings.Join(c.Gate.Modules, ",") != "gitea" {
+		t.Errorf("the gate names %v", c.Gate.Modules)
+	}
+	c = checkedOf(link.BuildResult{ID: "b", Ref: "abc", Checked: asked, Check: &link.CheckOutcome{Verdict: "warning", Summary: "wide"}})
+	if c.Gate == nil || c.Gate.Verdict != "warning" || c.RepoCheck != nil {
+		t.Fatalf("an outcome without layers said %+v", c)
+	}
+	c = checkedOf(link.BuildResult{ID: "b", Ref: "abc", Checked: asked, Check: &link.CheckOutcome{Verdict: "pass",
+		Gate: &link.CheckLayer{Verdict: "pass"}, RepoCheck: &link.CheckLayer{Verdict: "fail", Summary: "its merge-check.sh failed"}}})
+	if c.RepoCheck.Verdict != "fail" || c.Gate.Verdict != "pass" {
+		t.Fatalf("the layers said %+v / %+v", c.Gate, c.RepoCheck)
+	}
+}
+
+// **The check asks the planner, never a mapping of its own** (novox/hq ADR 0238): what a pull request
+// reaches is reachOfMerge's answer — the same that plans a merge — so a file at the root touches no
+// module in both, and what stands on a touched module is named as its dependents in both.
+func TestAPullRequestReachesWhatAMergeOfItWouldPlan(t *testing.T) {
+	const catalogue = "http://forge.internal:20000/novox/mesh-catalog.git"
+	nats := fromRepo("nats", catalogue, "modules/nats")
+	nats.Source.BuiltFrom = "old"
+	gitea := fromRepo("gitea", catalogue, "modules/gitea")
+	gitea.Source.BuiltFrom = "old"
+	tools := fromRepo("node-tools", "http://forge.internal:20000/novox/mesh-tools.git", "node-tools")
+	entries := []inventory.Entry{nats, gitea, tools}
+	// node-tools stands on the bus's image; a code edge, so a plan takes it along.
+	edges := []inventory.Edge{{From: "node-tools", To: "nats", Kind: inventory.EdgeStandsOn}}
+	read := map[string][]inventory.ReadRepository{}
+
+	for _, c := range []struct {
+		what              string
+		paths             []string
+		moved, dependents string
+		width             int
+		unread            string
+	}{
+		{"a file at the root, read by no build", []string{"merge-check.sh"}, "", "", 0, "merge-check.sh"},
+		{"the bus's own directory", []string{"modules/nats/Dockerfile"}, "nats", "node-tools", 2, ""},
+		{"both, and a README", []string{"modules/gitea/index.ts", "modules/nats/x", "README.md"}, "gitea,nats", "node-tools", 3, "README.md"},
+	} {
+		p := link.PullUpdated{Owner: "novox", Repo: "mesh-catalog", Base: "main", Commit: "head", Paths: c.paths}
+		s := pullScope(p, entries, read, edges)
+		m := link.SourceMoved{Owner: "novox", Repo: "mesh-catalog", Base: "main", Commit: "head", Paths: c.paths}
+		r := reachOfMerge(m, entries, read, edges)
+		if got := strings.Join(s.Modules, ","); got != c.moved || got != strings.Join(r.Moved(), ",") {
+			t.Errorf("%s: the check reaches %q, the planner %v, wanted %q", c.what, got, r.Moved(), c.moved)
+		}
+		if got := strings.Join(s.Dependents, ","); got != c.dependents {
+			t.Errorf("%s: dependents %q, wanted %q", c.what, got, c.dependents)
+		}
+		if s.Width != c.width || s.Width != len(r.Plan.Modules) {
+			t.Errorf("%s: a merge would build %d, the planner says %d, wanted %d", c.what, s.Width, len(r.Plan.Modules), c.width)
+		}
+		if got := strings.Join(s.Unread, ","); got != c.unread {
+			t.Errorf("%s: unread %q, wanted %q", c.what, got, c.unread)
+		}
+	}
+
+	// A repository whose build another module's recipe packages: that module is reached through the
+	// planner's `read`, and what stands on it after it.
+	read["gitea"] = []inventory.ReadRepository{{Repository: "http://forge.internal:20000/novox/mesh-sdk.git"}}
+	s := pullScope(link.PullUpdated{Owner: "novox", Repo: "mesh-sdk", Base: "main", Commit: "head",
+		Paths: []string{"src/index.ts"}}, entries, read, edges)
+	if strings.Join(s.Modules, ",") != "gitea" || len(s.Manifests) != 0 {
+		t.Fatalf("a change to the source gitea packages reaches %v (manifests %v)", s.Modules, s.Manifests)
+	}
+}
+
+// **Only a commit on the trunk is published** (novox/hq ADR 0238): a build of a commit off its repository's
+// default branch — a pull request's head, a branch built by hand, a rebuild or replay of one — is recorded
+// and never registered, so nothing can send it; a check or a dry run never is either.
+func TestABuildOffTheTrunkIsNeverPublished(t *testing.T) {
+	on := link.BuildResult{ID: "b", Commit: "abc", Trunk: "main", OnTrunk: true}
+	if err := publishable(on, ""); err != nil {
+		t.Errorf("a build on the trunk was refused: %v", err)
+	}
+	off := link.BuildResult{ID: "b", Commit: "abc", Trunk: "main"}
+	if err := publishable(off, ""); !errors.Is(err, errOffTheTrunk) || !strings.Contains(err.Error(), "main") {
+		t.Errorf("a build off the trunk was let through: %v", err)
+	}
+	for _, r := range []link.BuildResult{
+		{ID: "c", Trunk: "main", OnTrunk: true, Check: &link.CheckOutcome{Verdict: "pass"}},
+		{ID: "d", Trunk: "main", OnTrunk: true, Checked: &link.CheckRequest{}},
+		{ID: "e", Trunk: "main", OnTrunk: true, DryRun: true},
+	} {
+		if publishable(r, "") == nil {
+			t.Errorf("%s, a check or a dry run, was publishable", r.ID)
+		}
+	}
+	// A module that follows a branch other than the default: that branch is its trunk, and the default
+	// is not.
+	follows := link.BuildResult{ID: "g", Commit: "abc", Trunk: "master", Branches: []string{"nox-mesh"}}
+	if err := publishable(follows, "nox-mesh"); err != nil {
+		t.Errorf("a commit on the branch a module follows was refused: %v", err)
+	}
+	if err := publishable(link.BuildResult{ID: "h", Commit: "abc", Trunk: "master", OnTrunk: true,
+		Branches: []string{"master"}}, "nox-mesh"); err == nil {
+		t.Error("a commit on the default but not on the branch the module follows was published")
+	}
+	if err := publishable(link.BuildResult{ID: "i", Commit: "abc", Trunk: "main", Branches: []string{"feat/x"}}, ""); err == nil {
+		t.Error("a feature branch's commit was published")
+	}
+	// A build seat older than the rule says nothing: let through and said, so the rule can reach the mesh.
+	if err := publishable(link.BuildResult{ID: "f", Commit: "abc"}, ""); err != nil {
+		t.Errorf("a build seat that said nothing was refused: %v", err)
+	}
+}
+
+// **A verdict names the trunk commit it judged** (novox/hq ADR 0323 §3, issue 341): the controller's `checked`
+// carries the head and the trunk commit the build seat merged it into, the commits of the repositories read beside
+// it, how long it took, and the kept delivery plan records the trunk commit with its other inputs. A group's
+// composed check names, per member, the trunk commit that head was merged into (§6).
+func TestAVerdictNamesTheTrunkCommitItJudged(t *testing.T) {
+	plan := &link.ChangePlan{Repository: "novox/mesh-host", Base: "main", Head: "dfb1415aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+		Summary: "builds mesh-host"}
+	asked := &link.CheckRequest{Owner: "novox", Repo: "mesh-host", Number: 66, Base: "main", Plan: plan}
+	c := checkedOf(link.BuildResult{ID: "b", Ref: "dfb1415aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa", Checked: asked,
+		Check: &link.CheckOutcome{Verdict: "pass", Took: "4m12s", Head: "dfb1415aaaaa", Trunk: "d28ca95bbbbb",
+			Gate: &link.CheckLayer{Verdict: "pass"}, RepoCheck: &link.CheckLayer{Verdict: "pass"},
+			Beside: map[string]string{"mesh-catalog": "0123456789ab", "mesh-lab": "ba9876543210"}}})
+	if c.Trunk != "d28ca95bbbbb" || c.Commit != "dfb1415aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" {
+		t.Fatalf("the verdict names head %s and trunk %q", c.Commit, c.Trunk)
+	}
+	if c.Beside["mesh-catalog"] != "0123456789ab" || c.Beside["mesh-lab"] != "ba9876543210" {
+		t.Fatalf("the verdict names the repositories read beside it as %v", c.Beside)
+	}
+	if c.Took != "4m12s" {
+		t.Fatalf("the verdict says it took %q", c.Took)
+	}
+	if c.Plan == nil || c.Plan.Trunk != "d28ca95bbbbb" || c.Plan.Head != plan.Head {
+		t.Fatalf("the kept plan records %+v", c.Plan)
+	}
+	if plan.Trunk != "" {
+		t.Fatal("the plan the controller asked with was changed: the verdict's is a copy")
+	}
+
+	group := &link.CheckRequest{Owner: "novox", Repo: "mesh-controller", Number: 7, Base: "main", Group: "feat/x",
+		Members: []link.GroupMember{{Owner: "novox", Repo: "mesh-host", Number: 8, Ref: "cccccccccccc0000", Base: "main"}}}
+	c = checkedOf(link.BuildResult{ID: "g", Ref: "aaaaaaaaaaaa0000", Checked: group, Check: &link.CheckOutcome{
+		Verdict: "pass", Head: "aaaaaaaaaaaa", Trunk: "111111111111", Gate: &link.CheckLayer{Verdict: "pass"},
+		Members: []link.CheckedMember{{Owner: "novox", Repo: "mesh-host", Commit: "cccccccccccc", Trunk: "222222222222"}}}})
+	if len(c.Members) != 2 || c.Members[0].Trunk != "111111111111" || c.Members[1].Trunk != "222222222222" ||
+		c.Members[1].Commit != "cccccccccccc0000" {
+		t.Fatalf("the composed check names its members %+v", c.Members)
+	}
+}
+
+// **The merge made for a check is never registered** (novox/hq ADR 0323 §2): a build of it — a commit on no branch
+// of the forge — is refused, naming the trunk. The rule of ADR 0238 §1 stands unchanged; this holds it for the
+// merge commit a check makes.
+func TestABuildOfACheckMergeIsRefusedNamingTheTrunk(t *testing.T) {
+	merge := link.BuildResult{ID: "b", Commit: "4b5c6d7e8f90aabbccddeeff0011223344556677", Trunk: "main"}
+	err := publishable(merge, "")
+	if !errors.Is(err, errOffTheTrunk) || !strings.Contains(err.Error(), "not on main") {
+		t.Fatalf("a build of a check's merge was answered %v", err)
+	}
+}
+
+// **A verdict no build judges names its trunk commit too** (novox/hq ADR 0323 §3): a change touching no module of a
+// repository with no merge-check.sh (novox/mesh-tools-go) is answered by the controller itself. Naming no trunk, the
+// merge tool refused it, asked again, got the same verdict, and refused for ever.
+func TestADirectVerdictNamesTheTrunkTheForgeAnnounced(t *testing.T) {
+	p := link.PullUpdated{Owner: "novox", Repo: "mesh-tools-go", Number: 3, Base: "main", Commit: "1a2b3c4d5e6f7a8b9c0d",
+		BaseSHA: "7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b"}
+	c := directVerdict(p, link.ChangePlan{Repository: "novox/mesh-tools-go", Base: "main", Head: p.Commit})
+	if c.Trunk != "7a8b9c0d1e2f" || c.Plan == nil || c.Plan.Trunk != "7a8b9c0d1e2f" {
+		t.Fatalf("the direct verdict names trunk %q, its plan %+v", c.Trunk, c.Plan)
+	}
+	if c.Verdict != "pass" || c.Commit != p.Commit {
+		t.Fatalf("the direct verdict is %+v", c)
+	}
+	if c := directVerdict(link.PullUpdated{Owner: "novox", Repo: "x", Commit: "abc"}, link.ChangePlan{}); c.Trunk != "" {
+		t.Fatalf("a forge that said no base head gave the trunk %q", c.Trunk)
+	}
+}
+
+// A head checked again through mesh-delivery (`delivery check --members`, a recheck) reaches the same direct verdict:
+// it names the base head the forge last announced, kept on the member, or the merge tool would refuse it for ever.
+func TestARecheckedHeadsDirectVerdictNamesItsTrunk(t *testing.T) {
+	m := orderMember{ID: "novox/mesh-tools-go@1a2b3c4d5e6f", Repository: "novox/mesh-tools-go", Base: "main",
+		Head: "1a2b3c4d5e6f7a8b9c0d", Number: 3, BaseSHA: "7a8b9c0d1e2f3a4b5c6d7e8f9a0b1c2d3e4f5a6b"}
+	if c := directVerdict(m.pull(), link.ChangePlan{}); c.Trunk != "7a8b9c0d1e2f" {
+		t.Fatalf("a rechecked head's direct verdict names trunk %q", c.Trunk)
+	}
+}
+
+// A check stopped by its pull request's key moving on says no verdict (issue 974, review 2): an error said for it would name the
+// live head, and the newer request is the one that judges. A check that failed for any other reason still says its error.

cmd/mesh-controller/collect.go

@@ -0,0 +1,276 @@
+package main
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/novox/mesh-controller/internal/artifacts"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// Letting the artifact store go of what the mesh no longer keeps (novox/hq ADR 0189, issue 108).
+//
+// **Run where the records change.** A build is the moment new bytes landed in the store and the
+// moment the keep set moved, so it is the moment to say what may go — and it needs no timer of
+// its own. Reclaiming the bytes is the store's own nightly step; this only decides.
+//
+// **And run when a person asks** (novox/hq ADR 0251): the `collect` verb is the same sweep, with
+// bounds of its own. One implementation, so what a person runs is exactly what a build runs.
+//
+// Never fatal to a build. The build succeeded, the module is registered, and a store that could
+// not be reached is a thing to say rather than a reason to undo any of that. The next build asks
+// again, and the references it could not collect are still uncollected, so nothing is lost by
+// having failed.
+
+// sweepBounds is how much one sweep may ask of the store.
+type sweepBounds struct {
+	// most is how many artifacts it lets go of at most.
+	most int
+	// budget is the longest it keeps its caller waiting.
+	budget time.Duration
+	// platforms is whether an index is let go of with its own platform manifests (novox/hq ADR 0257).
+	// Only a sweep a person confirmed, after its dry run listed what stays and names a platform: the
+	// records cannot see an unrecorded index, or a copy in progress, naming the same platform, and the
+	// store's tools can.
+	platforms bool
+}
+
+// afterBuild are the bounds of the sweep inside somebody's build.
+//
+// **Bounded, because this runs inside somebody's build.** The first sweep of a mesh that has never
+// collected has the whole history to get through, and a person waiting on `build` should not pay for
+// it. What is left over is simply offered again next time — builds are frequent, and the point is
+// that the store stops growing, not that it empties tonight.
+var afterBuild = sweepBounds{most: mostPerSweep, budget: sweepBudget}
+
+// sweepResult is what one sweep did.
+type sweepResult struct {
+	// HoldersWritten is how many kept archives the store now holds by a manifest it did not before.
+	HoldersWritten int
+	// Missing is how many kept archives the store does not have at all.
+	Missing int
+	// Held is whether every kept archive could be asked to be held; false stops the sweep before it
+	// lets anything go.
+	Held bool
+	// LetGo is what the store let go of, and the record now says collected.
+	LetGo []string
+	// Skipped is how many references the sweep will not address (novox/hq issue 226).
+	Skipped int
+	// Indexes is how many eligible indexes a sweep a person did not confirm left for one that is: an
+	// index goes only with its platform manifests (novox/hq ADR 0257 §4).
+	Indexes int
+	// Left is how many eligible references were not asked about this time.
+	Left int
+	// Bounded is whether it stopped at its bounds rather than at a refusal.
+	Bounded bool
+	// Stopped says why the sweep stopped before the end; empty when it did not.
+	Stopped string
+}
+
+// sweep holds every kept archive, then asks the store to let go of each reference in order, records
+// what it let go of, and says what it did.
+func sweep(ctx context.Context, inv *inventory.Inventory, store artifacts.Store, references, kept []string,
+	bounds sweepBounds) sweepResult {
+	within, stop := context.WithTimeout(ctx, bounds.budget)
+	defer stop()
+	var r sweepResult
+
+	// **Hold before letting go** (novox/hq issue 253). The store's collector keeps only what a
+	// manifest names, and archives were published as bare blobs, so every kept archive is first
+	// held by its manifest — which backfills the ones published before holders, a few at a time
+	// as builds come, and is two HEADs each once done. A kept archive that could not be held stops
+	// the sweep before it deletes anything: "everything kept is held" is the precondition the
+	// collector's safety rests on, and a store refusing a hold would refuse the deletes too.
+	// **An index goes with its platform manifests only when a person confirmed it** (novox/hq ADR
+	// 0257), and a kept index keeps its own: which platform manifests the kept indexes name is read
+	// from the store for every repository the sweep will touch, before the first delete. A single
+	// read that fails stops the sweep before it deletes anything, as a kept archive that cannot be
+	// held does. The sweep after a build leaves an eligible index for such a collect, below.
+	store.Spare = nil
+	if bounds.platforms {
+		if inv == nil {
+			r.Stopped = "no records to read which platform manifests a kept index names, so nothing was let go"
+			r.Left = len(references)
+			return r
+		}
+		images, err := inv.KeptImages(ctx)
+		if err == nil {
+			store.Spare, err = store.SpareKeptIndexes(within, images, references)
+		}
+		if err != nil {
+			r.Stopped = fmt.Sprintf("which platform manifests a kept index names could not be read, so nothing was let go: %v", err)
+			r.Left = len(references)
+			return r
+		}
+	}
+
+	wrote, missing, err := holdKept(within, store, kept)
+	r.HoldersWritten, r.Missing = wrote, missing
+	if err != nil {
+		r.Stopped = fmt.Sprintf("not every kept archive could be held, so nothing was let go: %v", err)
+		r.Left = len(references)
+		return r
+	}
+	r.Held = true
+
+	for i, reference := range references {
+		if i >= bounds.most || within.Err() != nil {
+			r.Left = len(references) - i
+			r.Bounded = true
+			if i >= bounds.most {
+				r.Stopped = fmt.Sprintf("asked about %d, the most one sweep asks", bounds.most)
+			} else {
+				r.Stopped = fmt.Sprintf("ran out of its %s", bounds.budget)
+			}
+			break
+		}
+		if !bounds.platforms {
+			// **An index waits for a confirmed collect** (novox/hq ADR 0257 §4). Let go of alone,
+			// its platform manifests would stay in the store and the record would say collected, so
+			// no later sweep would offer it again and they would stay for ever. Left eligible, the
+			// next collect a person confirms takes it with them.
+			index, err := store.IsIndex(within, reference)
+			if err != nil && !errors.Is(err, artifacts.Gone) && !errors.Is(err, artifacts.ErrNotOurs) {
+				r.Stopped = fmt.Sprintf("the artifact store could not say whether %s is an index, so nothing more was asked of it: %v", reference, err)
+				r.Left = len(references) - i
+				break
+			}
+			if index {
+				r.Indexes++
+				continue
+			}
+		}
+		err := store.LetGo(within, reference)
+		if err == nil || errors.Is(err, artifacts.Gone) {
+			// Gone is the outcome wanted, already true. Recorded so the next sweep does not ask
+			// again for ever.
+			r.LetGo = append(r.LetGo, reference)
+			continue
+		}
+		if errors.Is(err, artifacts.ErrNotOurs) {
+			// **A fact about this record, so this record is skipped** (novox/hq issue 226). Not
+			// marked collected — the mesh did not remove it and should not claim to — and not a
+			// reason to stop, because the store was never asked. One of these at the front of
+			// the oldest-first order ended every sweep until this.
+			r.Skipped++
+			if r.Skipped == 1 {
+				fmt.Fprintf(os.Stderr, "the sweep will not address %s and went on: %v\n", reference, err)
+			}
+			continue
+		}
+		// **Stopped at the first refusal by the STORE, not pushed through.** A store that refuses
+		// one refuses all of them — deletion disabled, the store down, the network gone — so
+		// going on would be a hundred identical failures and a hundred identical log lines in
+		// front of whoever was building something.
+		r.Stopped = fmt.Sprintf("the artifact store kept %s, so nothing more was asked of it: %v", reference, err)
+		r.Left = len(references) - i
+		break
+	}
+
+	if len(r.LetGo) > 0 {
+		// Recorded outside `within`: the deletions happened, and losing the record of them because
+		// the sweep ran out of budget would mean asking about them again for ever.
+		if err := inv.MarkCollected(ctx, r.LetGo); err != nil {
+			r.Stopped = fmt.Sprintf("the store let go of %d artifact(s) and the record of it did not keep: %v",
+				len(r.LetGo), err)
+		}
+	}
+	return r
+}
+
+// collect asks the store to let go of everything the mesh made and no longer keeps, and records
+// what it let go of — after a build. Says what it did and what it could not; returns nothing,
+// because nothing upstream should branch on it.
+func collect(ctx context.Context, inv *inventory.Inventory) {
+	references, err := inv.ToCollect(ctx)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "could not work out what the artifact store may let go of: %v\n", err)
+		return
+	}
+	kept, err := inv.KeptArchives(ctx)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "could not work out which archives the artifact store keeps: %v\n", err)
+		return
+	}
+	if len(references) == 0 && len(kept) == 0 {
+		return
+	}
+	shelf, err := inv.Catalogue(ctx)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "could not read the catalogue to find the artifact store: %v\n", err)
+		return
+	}
+	// As the mesh reaches it from the network. Empty means the store is not on the network — on a
+	// mesh being raised it is not yet, and there the store holds one build of anything and has
+	// nothing to collect.
+	address, err := artifactStoreAddress(ctx, inv, shelf, "")
+	if err != nil || address == "" {
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "could not find the artifact store to collect from: %v\n", err)
+		}
+		return
+	}
+
+	r := sweep(ctx, inv, artifacts.Store{Address: address}, references, kept, afterBuild)
+	if r.HoldersWritten > 0 {
+		fmt.Fprintf(os.Stderr, "the artifact store now holds %d more kept archive(s) by a manifest\n", r.HoldersWritten)
+	}
+	if r.Missing > 0 {
+		fmt.Fprintf(os.Stderr, "%d archive(s) the mesh keeps are not in the artifact store at all; "+
+			"`collection` lists them\n", r.Missing)
+	}
+	if len(r.LetGo) > 0 {
+		fmt.Fprintf(os.Stderr, "the artifact store let go of %d artifact(s) the mesh no longer keeps\n", len(r.LetGo))
+	}
+	if r.Stopped != "" && !r.Bounded {
+		fmt.Fprintln(os.Stderr, r.Stopped)
+	}
+	if r.Held && r.Left > 0 {
+		fmt.Fprintf(os.Stderr, "%d more to collect; the next build asks again\n", r.Left)
+	}
+	if r.Skipped > 0 {
+		fmt.Fprintf(os.Stderr, "%d artifact(s) the sweep will not address were skipped\n", r.Skipped)
+	}
+	if r.Indexes > 0 {
+		fmt.Fprintf(os.Stderr, "%d eligible index(es) wait for a collect a person confirms, which takes their platforms too\n", r.Indexes)
+	}
+}
+
+// holdKept holds every kept archive by its manifest, stopping at the first refusal by the store.
+// Answers how many holders it wrote and how many kept archives the store does not have.
+//
+// A missing archive is counted rather than fatal: there is nothing to hold, and that is a fact
+// for an operator to read (`collection`), not a reason to stop collecting what is not kept. A
+// reference the store cannot be asked about is skipped as the deletion loop skips one
+// (novox/hq issue 226).
+func holdKept(ctx context.Context, store artifacts.Store, kept []string) (wrote, missing int, err error) {
+	for _, reference := range kept {
+		if err := ctx.Err(); err != nil {
+			return wrote, missing, fmt.Errorf("ran out of time before %s: %w", reference, err)
+		}
+		did, err := store.Hold(ctx, reference)
+		switch {
+		case err == nil:
+			if did {
+				wrote++
+			}
+		case errors.Is(err, artifacts.Gone):
+			missing++
+		case errors.Is(err, artifacts.ErrNotOurs):
+		default:
+			return wrote, missing, fmt.Errorf("holding %s: %w", reference, err)
+		}
+	}
+	return wrote, missing, nil
+}
+
+// mostPerSweep is how many artifacts one sweep will ask about. Enough that a mesh building
+// several times a day converges within days of this landing; small enough that no single build
+// waits on the whole backlog.
+const mostPerSweep = 200
+
+// sweepBudget is the longest a sweep will keep a build waiting.
+const sweepBudget = 60 * time.Second

cmd/mesh-controller/collection.go

@@ -0,0 +1,166 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"flag"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/novox/mesh-controller/internal/artifacts"
+)
+
+// What the artifact store keeps, whether each kept archive is held, and what the sweep may let go
+// (novox/hq issue 253, ADR 0189).
+//
+// **The question to answer before the store's collector runs for real.** The collector deletes
+// every blob no manifest names, and archives were published as bare blobs, so the nightly step
+// runs `--dry-run` until every archive the mesh keeps is held by its manifest. The sweep holds
+// them as builds come; this says how far that has got — "0 unheld" is the number that lets the
+// dry run go.
+//
+// Reads and changes nothing: each kept archive is asked about with HEADs only. Reached over the
+// console through the mesh-controller seat's `command` verb (`collection --json`), which needs no
+// new verb in the seat's row.
+
+type collectionReport struct {
+	// Store is the artifact store as this machine reached it; empty when it is not on the network.
+	Store string `json:"store"`
+	// KeptArchives is how many archives the mesh keeps, for either reason.
+	KeptArchives int `json:"kept_archives"`
+	// Held is how many of them the store holds by their manifest.
+	Held int `json:"held"`
+	// Unheld are the kept archives the collector would delete tonight if it ran for real.
+	Unheld []string `json:"unheld"`
+	// Missing are kept archives the store does not have at all.
+	Missing []string `json:"missing"`
+	// Unasked is how many could not be asked about, and why the asking stopped.
+	Unasked int    `json:"unasked"`
+	Stopped string `json:"stopped,omitempty"`
+	// Eligible is what the sweep may let go of: made by the mesh, kept for no reason, not yet
+	// collected — split by kind.
+	Eligible         int `json:"eligible"`
+	EligibleImages   int `json:"eligible_images"`
+	EligibleArchives int `json:"eligible_archives"`
+	// SafeToCollect is whether every kept archive was asked about and every one is held.
+	SafeToCollect bool `json:"safe_to_collect"`
+}
+
+func collectionCommand(ctx context.Context, args []string) error {
+	set := flag.NewFlagSet("collection", flag.ContinueOnError)
+	asJSON := set.Bool("json", false, "answer as JSON")
+	positionals, err := parseAround(set, args)
+	if err != nil {
+		return err
+	}
+	if len(positionals) != 0 {
+		return errors.New("collection [--json]")
+	}
+
+	open, err := openStores(ctx)
+	if err != nil {
+		return err
+	}
+	defer open.Close()
+	inv := open.inventory
+
+	kept, err := inv.KeptArchives(ctx)
+	if err != nil {
+		return err
+	}
+	eligible, err := inv.ToCollect(ctx)
+	if err != nil {
+		return err
+	}
+	report := collectionReport{KeptArchives: len(kept), Eligible: len(eligible), Unheld: []string{}, Missing: []string{}}
+	for _, reference := range eligible {
+		if strings.Contains(reference, "/blobs/") {
+			report.EligibleArchives++
+		} else {
+			report.EligibleImages++
+		}
+	}
+
+	shelf, err := inv.Catalogue(ctx)
+	if err != nil {
+		return err
+	}
+	report.Store, err = artifactStoreAddress(ctx, inv, shelf, "")
+	if err != nil {
+		return err
+	}
+	if report.Store == "" {
+		report.Unasked = len(kept)
+		report.Stopped = "this mesh has no artifact store on its network"
+	} else {
+		report.Unasked, report.Stopped = askHeld(ctx, artifacts.Store{Address: report.Store}, kept, &report)
+	}
+	report.SafeToCollect = report.Unasked == 0 && len(report.Unheld) == 0
+
+	if *asJSON {
+		encoder := json.NewEncoder(os.Stdout)
+		encoder.SetIndent("", "  ")
+		return encoder.Encode(report)
+	}
+	printCollection(report)
+	return nil
+}
+
+// askHeld asks the store about each kept archive, stopping at the first answer that is not about
+// the archive: a store that cannot be reached for one cannot be for the next, and a page of
+// identical failures says less than one line.
+func askHeld(ctx context.Context, store artifacts.Store, kept []string, report *collectionReport) (int, string) {
+	for i, reference := range kept {
+		held, err := store.Held(ctx, reference)
+		switch {
+		case err == nil && held:
+			report.Held++
+		case err == nil:
+			report.Unheld = append(report.Unheld, reference)
+		case errors.Is(err, artifacts.Gone):
+			report.Missing = append(report.Missing, reference)
+		case errors.Is(err, artifacts.ErrNotOurs):
+			// KeptArchives names only the mesh's own; counted as unasked if one ever is not.
+			report.Unasked++
+		default:
+			return report.Unasked + len(kept) - i, fmt.Sprintf("asking about %s: %v", reference, err)
+		}
+	}
+	return report.Unasked, ""
+}
+
+func printCollection(r collectionReport) {
+	store := r.Store
+	if store == "" {
+		store = "(not on the network)"
+	}
+	fmt.Printf("artifact store       %s\n", store)
+	fmt.Printf("kept archives        %d\n", r.KeptArchives)
+	fmt.Printf("  held               %d\n", r.Held)
+	fmt.Printf("  unheld             %d\n", len(r.Unheld))
+	fmt.Printf("  missing            %d\n", len(r.Missing))
+	if r.Unasked > 0 {
+		fmt.Printf("  not asked          %d (%s)\n", r.Unasked, r.Stopped)
+	}
+	fmt.Printf("eligible to let go   %d (%d images, %d archives)\n", r.Eligible, r.EligibleImages, r.EligibleArchives)
+	if len(r.Unheld) > 0 {
+		fmt.Println("\nunheld — the store's collector would delete these; the next build's sweep holds them:")
+		for _, reference := range r.Unheld {
+			fmt.Printf("  %s\n", reference)
+		}
+	}
+	if len(r.Missing) > 0 {
+		fmt.Println("\nmissing — kept by the mesh, not in the store:")
+		for _, reference := range r.Missing {
+			fmt.Printf("  %s\n", reference)
+		}
+	}
+	fmt.Println()
+	if r.SafeToCollect {
+		fmt.Println("every kept archive is held: the store's collector may run for real")
+	} else {
+		fmt.Println("NOT every kept archive is known to be held: keep the store's collector on --dry-run")
+	}
+}

cmd/mesh-controller/composed_member_check_test.go

@@ -0,0 +1,68 @@
+//go:build integration
+
+package main
+
+import (
+	"context"
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// A member of a group whose gate is the composed check's is asked of the build seat with no module: its repository's
+// check alone (novox/hq ADR 0403 clause 1). With no word from mesh-delivery, or one that does not say the gate is
+// composed, it is checked alone with its gate (clause 6).
+
+func askedForMember(t *testing.T, answer []groupsLine, answerErr error) link.CheckRequest {
+	t.Helper()
+	open := aMesh(t)
+	ctx := t.Context()
+	js, _ := aBuildQueue(t)
+	servingBus.Store(js)
+	t.Cleanup(func() { servingBus.Store(nil) })
+	if err := open.inventory.RegisterModule(ctx, catalogue.Manifest{Module: "mesh-controller", Version: "1"},
+		inventory.Source{Repository: "novox/mesh-controller", Ref: "main", BuiltFrom: "c0", Head: "c0"}); err != nil {
+		t.Fatal(err)
+	}
+	was := groupsAsked
+	groupsAsked = func(context.Context, bool) ([]groupsLine, error) { return answer, answerErr }
+	t.Cleanup(func() { groupsAsked = was })
+	p := link.PullUpdated{Owner: "novox", Repo: "mesh-controller", Number: 346, Base: "main", Head: "feat/x", Commit: headController,
+		Paths: []string{"main.go"}, ModuleDirsSaid: true, MergeCheck: true, MergeCheckSaid: true}
+	if err := (following{open: open, oneShot: true}).PullUpdated(ctx, p); err != nil {
+		t.Fatal(err)
+	}
+	q, err := link.ReadQueue(ctx, js, link.TheBuildMachine)
+	if err != nil || len(q.Asks) != 1 {
+		t.Fatalf("asks %d: %v", len(q.Asks), err)
+	}
+	return *q.Asks[0].Request.Check
+}
+
+func TestAComposedMembersCheckIsItsRepositoryChecksAlone(t *testing.T) {
+	line := group("feat/x", member("novox/mesh-controller", 346, headController, "main", true), member("novox/mesh-catalog", 350, headHost, "main", true))
+	line.ComposedGate = true
+	c := askedForMember(t, []groupsLine{line}, nil)
+	if len(c.Modules) != 0 || len(c.New) != 0 || len(c.Dependents) != 0 || !c.Composed {
+		t.Fatalf("the member's check is asked as %+v; want no module and composed", c)
+	}
+}
+
+func TestAMemberOfAGroupOfAnOlderMeshDeliveryKeepsItsOwnGate(t *testing.T) {
+	line := group("feat/x", member("novox/mesh-controller", 346, headController, "main", true), member("novox/mesh-catalog", 350, headHost, "main", true))
+	c := askedForMember(t, []groupsLine{line}, nil)
+	if !strings.Contains(strings.Join(c.Modules, ","), "mesh-controller") || c.Composed {
+		t.Fatalf("an older mesh-delivery's member is asked as %+v; want its own gate", c)
+	}
+}
+
+func TestAMemberWhoseGroupCannotBeLearnedIsCheckedAloneWithItsGate(t *testing.T) {
+	c := askedForMember(t, nil, context.DeadlineExceeded)
+	if !strings.Contains(strings.Join(c.Modules, ","), "mesh-controller") || c.Composed ||
+		!strings.Contains(c.SiblingsUnknown, "reads no siblings") {
+		t.Fatalf("the member is asked as %+v; want its gate and why its siblings are unknown", c)
+	}
+}

cmd/mesh-controller/composed_verdict_test.go

@@ -0,0 +1,136 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"strings"
+	"testing"
+
+	"github.com/novox/mesh-controller/internal/catalogue"
+	"github.com/novox/mesh-controller/internal/inventory"
+	"github.com/novox/mesh-controller/internal/link"
+)
+
+// A delivery group's gate is the composed check's, and its members' own checks run their repository's check alone
+// (novox/hq ADR 0403 clauses 1 and 7). Pure: no store, no bus.
+
+// A member of a group whose line says composed_gate is a composed member; one whose group says nothing of it (an older
+// mesh-delivery), one of a group of a single pull request and a lone pull request are not.
+func TestAMemberOfAComposedGroupIsKnownByTheGroupsLine(t *testing.T) {
+	two := func(composed bool) groupsLine {
+		l := group("feat/x", member("novox/mesh-host", 114, headHost, "main", true), member("novox/mesh-controller", 346, headController, "main", true))
+		l.ComposedGate = composed
+		return l
+	}
+	p := link.PullUpdated{Owner: "novox", Repo: "mesh-host", Number: 114, Base: "main", Head: "feat/x", Commit: headHost}
+	recheck := link.PullUpdated{Owner: "novox", Repo: "mesh-host", Number: 114, Base: "main", Commit: headHost}
+	for name, c := range map[string]struct {
+		p     link.PullUpdated
+		lines []groupsLine
+		want  bool
+	}{
+		"composed":                 {p, []groupsLine{two(true)}, true},
+		"a recheck, by its number": {recheck, []groupsLine{two(true)}, true},
+		"an older mesh-delivery":   {p, []groupsLine{two(false)}, false},
+		"another group":            {p, []groupsLine{group("feat/y", member("novox/mesh-host", 1, headHost, "main", true))}, false},
+		"no group":                 {p, nil, false},
+	} {
+		if got := composedMember(c.p, c.lines); got != c.want {
+			t.Errorf("%s: composed %v, want %v", name, got, c.want)
+		}
+	}
+	alone := group("feat/x", member("novox/mesh-host", 114, headHost, "main", true))
+	alone.ComposedGate = true
+	if composedMember(p, []groupsLine{alone}) {
+		t.Error("a group of a single pull request is composed")
+	}
+}
+
+// A composed member's verdict never says its gate passed: the gate layer, and the verdict that is the gate's, read
+// "composed"; a failure or an error stays what it was.
+func TestAComposedMembersVerdictHasNoPassingGate(t *testing.T) {
+	asked := &link.CheckRequest{Owner: "novox", Repo: "mesh-host", Number: 114, Composed: true}
+	pass := link.BuildResult{ID: "b", Ref: headHost, Checked: asked, Check: &link.CheckOutcome{Verdict: "pass", Summary: "no module touched",
+		Gate: &link.CheckLayer{Verdict: "pass", Summary: "no module touched"}, RepoCheck: &link.CheckLayer{Verdict: "pass", Summary: "ok"}}}
+	c := checkedOf(pass)
+	if c.Gate == nil || c.Gate.Verdict != "composed" || c.Verdict != "composed" || c.RepoCheck == nil || c.RepoCheck.Verdict != "pass" {
+		t.Fatalf("the member's verdict says %+v gate %+v", c, c.Gate)
+	}
+	asked.Composed = false
+	if c := checkedOf(pass); c.Gate.Verdict != "pass" || c.Verdict != "pass" {
+		t.Fatalf("a member of no composed group has its own gate: %+v", c.Gate)
+	}
+	asked.Composed = true
+	failing := pass
+	failing.Check = &link.CheckOutcome{Verdict: "fail", Summary: "conflict", Gate: &link.CheckLayer{Verdict: "fail", Summary: "conflict"},
+		RepoCheck: &link.CheckLayer{Verdict: "fail", Summary: "conflict"}}
+	if c := checkedOf(failing); c.Gate.Verdict != "fail" || c.Verdict != "fail" {
+		t.Fatalf("a failure was read as composed: %+v", c.Gate)
+	}
+	broken := link.BuildResult{ID: "b", Ref: headHost, Checked: asked, Failed: "the facts snapshot cannot be read"}
+	if c := checkedOf(broken); c.Verdict != "error" || c.Gate.Verdict != "error" {
+		t.Fatalf("an error was read as composed: %+v", c)
+	}
+}
+
+// The composed verdict on the bus carries every member, each with its trunk commit, for the forge's holder to set each
+// member's mesh/merge-gate from it.
+func TestTheComposedVerdictCarriesEveryMember(t *testing.T) {
+	asked := &link.CheckRequest{Owner: "novox", Repo: "mesh-host", Number: 114, Group: "feat/x",
+		Members: []link.GroupMember{{Owner: "novox", Repo: "mesh-controller", Number: 346, Ref: headController}}}
+	c := checkedOf(link.BuildResult{ID: "g", Ref: headHost, Checked: asked, Check: &link.CheckOutcome{Verdict: "pass", Summary: "ok",
+		Trunk: "aaaaaaaaaaaa", Members: []link.CheckedMember{{Owner: "novox", Repo: "mesh-controller", Commit: headController[:12], Trunk: "bbbbbbbbbbbb"}}}})
+	body, _ := json.Marshal(c)
+	for _, want := range []string{`"group":"feat/x"`, `"members":[{"owner":"novox","repo":"mesh-host","number":114,"commit":"` + headHost + `","trunk":"aaaaaaaaaaaa"}`,
+		`{"owner":"novox","repo":"mesh-controller","number":346,"commit":"` + headController + `","trunk":"bbbbbbbbbbbb"}`} {
+		if !strings.Contains(string(body), want) {
+			t.Fatalf("the composed verdict lacks %s:\n%s", want, body)
+		}
+	}
+}
+
+// Members whose manifests order their modules in a cycle fail the composed check, naming every module and edge, and no
+// ask is made of the build seat.
+func TestAGroupInACycleFailsItsComposedCheckWithoutABuild(t *testing.T) {
+	members := []orderMember{
+		{ID: "novox/x@" + headHost[:12], Repository: "novox/x", Base: "main", Head: headHost, Number: 7, Paths: []string{"module.json"}},
+		{ID: "novox/y@" + headController[:12], Repository: "novox/y", Base: "main", Head: headController, Number: 9, Paths: []string{"module.json"}},
+	}
+	reach := map[string]orderReach{members[0].ID: {Moved: []string{"mx"}}, members[1].ID: {Moved: []string{"my"}}}
+	was, wasParent := manifestAt, parentOf
+	t.Cleanup(func() { manifestAt, parentOf = was, wasParent })
+	parentOf = func(context.Context, string, string, string) (string, error) { return "", nil }
+	manifestAt = func(_ context.Context, _, repo, _, ref string) (catalogue.Manifest, bool, error) {
+		if ref == "main" {
+			return catalogue.Manifest{}, false, nil // what the pull requests merge into holds no such manifest
+		}
+		if repo == "x" {
+			return catalogue.Manifest{Module: "mx", DefinesSeats: []catalogue.SeatDeclaration{{Name: "s", Serves: []catalogue.Verb{{Name: "a"}}}},
+				Invokes: []string{"seat:s.b"}}, true, nil
+		}
+		return catalogue.Manifest{Module: "my", DefinesSeats: []catalogue.SeatDeclaration{{Name: "s", Serves: []catalogue.Verb{{Name: "b"}}}},
+			Invokes: []string{"seat:s.a"}}, true, nil
+	}
+	c, cyclic, err := cycleVerdict(context.Background(), "feat/cycle", members, reach, []inventory.Edge(nil), nil)
+	if err != nil || !cyclic {
+		t.Fatalf("no cycle found: %v", err)
+	}
+	if c.Verdict != "fail" || c.Group != "feat/cycle" || len(c.Members) != 2 || c.Gate == nil || c.Gate.Verdict != "fail" {
+		t.Fatalf("the verdict is %+v", c)
+	}
+	for _, w := range []string{"mx", "my", "s.a", "s.b"} {
+		if !strings.Contains(c.Summary, w) {
+			t.Errorf("the cycle does not name %s: %s", w, c.Summary)
+		}
+	}
+	// Members with no edge between them are no cycle.
+	manifestsReadMu.Lock()
+	clear(manifestsRead)
+	manifestsReadMu.Unlock()
+	manifestAt = func(context.Context, string, string, string, string) (catalogue.Manifest, bool, error) {
+		return catalogue.Manifest{}, false, nil
+	}
+	if _, cyclic, err := cycleVerdict(context.Background(), "feat/cycle", members, reach, nil, nil); err != nil || cyclic {
+		t.Fatalf("a cycle where there is none: %v %v", cyclic, err)
+	}
+}

cmd/mesh-controller/condition_looks.go

@@ -0,0 +1,76 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+
+	"github.com/novox/mesh-controller/internal/conditions"
+	"github.com/novox/mesh-controller/internal/inventory"
+)
+
+// The looks of the open conditions — how often each was observed, when last, its newest evidence — are
+// kept in the controller's store, not the conditions bucket (novox/hq issue 420, ADR 0289 §1): the bucket
+// is written when what a condition says changes, never for a look that saw it as it was.
+
+// storeLooks keeps the conditions' looks in the inventory.
+type storeLooks struct{ inv *inventory.Inventory }
+
+func (s storeLooks) KeepLooks(ctx context.Context, key string, l conditions.Looks) error {
+	evidence, err := json.Marshal(l.Evidence)
+	if err != nil {
+		return err
+	}
+	return s.inv.KeepConditionLooks(ctx, inventory.ConditionLooks{Key: key, Observations: l.Observations,
+		LastObserved: l.LastObserved, Evidence: evidence})
+}
+
+func (s storeLooks) Looked(ctx context.Context, key string) (conditions.Looks, bool, error) {
+	row, kept, err := s.inv.ConditionLooksOf(ctx, key)
+	if err != nil || !kept {
+		return conditions.Looks{}, kept, err
+	}
+	l, err := looksOf(row)
+	return l, err == nil, err
+}
+
+func (s storeLooks) AllLooks(ctx context.Context) (map[string]conditions.Looks, error) {
+	rows, err := s.inv.AllConditionLooks(ctx)
+	if err != nil {
+		return nil, err
+	}
+	out := make(map[string]conditions.Looks, len(rows))
+	for key, row := range rows {
+		l, err := looksOf(row)
+		if err != nil {
+			return nil, err
+		}
+		out[key] = l
+	}
+	return out, nil
+}
+
+func (s storeLooks) ForgetLooks(ctx context.Context, key string) error {
+	return s.inv.ForgetConditionLooks(ctx, key)
+}
+
+func looksOf(row inventory.ConditionLooks) (conditions.Looks, error) {
+	l := conditions.Looks{Observations: row.Observations, LastObserved: row.LastObserved.UTC()}
+	if len(row.Evidence) > 0 {
+		if err := json.Unmarshal(row.Evidence, &l.Evidence); err != nil {
+			return conditions.Looks{}, fmt.Errorf("the evidence kept for the condition %s cannot be read: %w", row.Key, err)
+		}
+	}
+	return l, nil
+}
+
+// looksHere is where a process that is not the serving controller reads the conditions' looks: the store,
+// opened for it, closed by the function returned. A store that cannot be opened is said on every condition
+// read through it, never read as none.
+func looksHere(ctx context.Context) (conditions.LookStore, func()) {
+	inv, err := openInventory(ctx)
+	if err != nil {
+		return conditions.NoLooks{Err: err}, func() {}
+	}
+	return storeLooks{inv}, inv.Close
+}